The Conservatives have suffered two by-election defeats in what had been seen as protected seats.
Labour won within the constituency of Selby and Ainsty, whereas the Liberal Democrats triumphed in Somerton and Frome.
The opposition events each overturned Tory majorities of about 20,000 - as polling specialists mentioned the outcomes meant "deep electoral trouble" for the Conservatives.
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Rishi Sunak mentioned the subsequent common election was not a "done deal" as his celebration was capable of narrowly maintain on to Boris Johnson's previous Uxbridge and South Ruislip seat. Despite predictions of a Labour victory in west London, Mayor Sadiq Khan's plan to increase the Ultra Low Emission Zone (ULEZ) to the capital's outer borough angered individuals on the doorstep.
So is Labour heading in the right direction to win energy and the way a lot are Mr Sunak's predecessors Liz Truss and Mr Johnson accountable for the PM's woes? Chief political correspondent Jon Craig and political correspondents Tamara Cohen and Rob Powell have been answering readers' questions on the by-election outcomes.
:: Is Labour set to win the subsequent election?
Tamara Cohen: Well, the brief reply is it is trying encouraging for Labour, nevertheless it's tough to foretell common election outcomes from by-elections, particularly when the overall election could possibly be greater than a 12 months away.
But the clear swing is away from the Tories in three very totally different elements of the nation. Labour wants a 12% swing nationally for a majority; and even when what we noticed in Uxbridge and South Ruislip is replicated nationally they could possibly be the most important celebration in a hung parliament.
But there's a lengthy option to go and the extent of Labour's restoration in Scotland - nonetheless untested - shall be essential.
:: Have Truss and Johnson doomed Sunak?
Rob Powell: Boris Johnson and Liz Truss have inflicted quite a lot of injury to the Tory model and that's undoubtedly harming the present authorities.
Polling exhibits voters blaming the Tories for spiralling mortgage prices and never trying fondly on the chaos of the previous couple of years.
So far, Rishi Sunak has spent quite a lot of time steadying the ship and placing out fires.
But he'll want to start out providing extra of a imaginative and prescient for what he needs to do for the nation if he needs to keep away from a thumping defeat subsequent 12 months. No 10 is suggesting that section of his premiership will begin after the summer season.
Labour can be dealing with an identical drawback, although.
Sir Keir Starmer spent the primary half of his time in workplace making an attempt to revive Labour as a reputable celebration of presidency within the eyes of many citizens. While that is labored to an extent, pollsters say many complain that they nonetheless do not know what he believes in or stands for.
Some Labour MPs and commerce unions need him to put out a extra stable plan as properly and never simply stand again and hope the Tories lose the subsequent election.
:: Will there be an imminent reshuffle, with the PM altering his high group?
Tamara Cohen: From what I'm listening to, no.
The factor about reshuffles is you by no means actually know when they'll occur, however whereas each the Conservatives and Labour will need to refresh their high groups earlier than the election, doing so after an evening that each try to spin as a victory seems like panic.
:: Will constituency modifications have an effect on the subsequent common election?
Jon Craig: Oh sure! Most definitely. And sarcastically, two of the most important casualties are seats contested on this week's by-elections: Somerton and Frome, and Selby and Ainsty.
The purpose of boundary modifications is to mirror modifications in inhabitants as, historically, internal metropolis constituencies lose voters and the suburbs and cities with new housing acquire them.
The thought is that every constituency ought to have between roughly 70,000 and 77,000 voters. That means some rural seats are huge, with claims that they've extra sheep than voters.
This time there's been a giant shake-up as a result of the boundaries have not modified since 2010 and solely 65 of the 650 Westminster seats shall be unchanged.
Somerton and Frome is being carved in two new constituencies, Glastonbury and Somerton, and Frome and East Somerset.
Selby and Ainsty is being cut up 4 methods, although most of its voters will keep in a brand new Selby constituency. Uxbridge and South Ruislip, alternatively, is affected by solely minor modifications.
Reflecting inhabitants strikes, the East Midlands, east of England, London, the South East and South West get extra seats. The North West, North East and West Midlands could have fewer, and Yorkshire retains the identical.
Normally, governments be sure that their celebration advantages from boundary modifications.
This time isn't any totally different. It's estimated that the Tories will profit by 5 or 10 seats on account of the modifications.
:: Does the Liberal Democrats' victory in Somerton and Frome present they're set for a giant comeback?
Rob Powell: Before being decimated after the coalition years with the Tories, the South West was a heartland for the Lib Dems.
This win - mixed with related victories in native elections within the space - suggests the dangerous style left by the coalition has pale and voters listed below are ready to provide them a go once more.
That does not imply all 4 of the Lib Dem MPs who gained their seats in by-elections within the final two years or so will retain them on the common election.
But the outcomes do recommend the Lib Dems can count on to financial institution some wins within the broader area subsequent 12 months.
So count on the Lib Dems to border themselves as the principle challenger to kick the Tories out in goal constituencies.
They'll select native insurance policies to marketing campaign on, in addition to persevering with to give attention to nationwide points such because the NHS and price of residing.
:: How possible is a snap common election?
Jon Craig: The subsequent election needs to be referred to as inside 5 years of the final.
That means it may, in concept, be as late as January 2025, for the reason that final one was in December 2019.
What usually triggers an early common election is when a authorities begins dropping votes within the Commons, culminating in dropping a vote of no confidence within the authorities, as occurred to James Callaghan's authorities in 1979.
But regardless of all Rishi Sunak's present difficulties, his authorities is not dropping any Commons votes, partly as a result of each time he faces a giant Tory revolt he caves in and geese a conflict together with his backbenchers.
So with inflation now starting to fall, Mr Sunak clearly feels completely entitled to say, as he did final month: "We've got to hold our nerve, stick to the plan and we will get through this."
Opposition leaders all the time demand a common election instantly and Sir Keir Starmer isn't any exception. But it ain't going to occur whereas Mr Sunak has a hefty majority in parliament.
:: Is there going to be a deal between Labour and the Liberal Democrats?
Rob Powell: If you are speaking about tactical voting, then each leaders insist they don't seem to be stepping apart to permit different events by.
On the probabilities of the 2 events forming a coalition after the subsequent election, I'm not satisfied something stable has been reached behind the scenes, however be in little question it will likely be on the minds of each leaders, as a result of the probabilities of Labour ending up as the most important celebration however with no majority are excessive.
Lib Dem success is already bringing questions on whether or not they would help a Labour authorities into energy.
Sir Ed Davey is not eager to speak about that, however notably did not rule it out at present after I requested him about it a number of instances.
Labour chief Sir Keir Starmer can be very woolly on the topic as whereas he is explicitly mentioned no take care of the SNP, the potential for teaming up with the Lib Dems is extra imprecise.
So either side are leaving the choices open. Expect inquiries to get extra pointed as polling day nears.
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:: Will events wrestle to implement inexperienced insurance policies after the impression of ULEZ in Uxbridge?
Tamara Cohen: That's a extremely good query, and one Labour are grappling with.
Angela Rayner mentioned low emission zones remained the correct thought, however her celebration wanted to mirror on assist individuals "do the right thing" with out penalising those that cannot afford a brand new automobile.
Whether it is Tory battles over wind farms, visitors schemes or the transfer to electrical vehicles, these contests are a warning to each events that they're going to have to take voters with them on environmental insurance policies.
:: Does Labour have the ability to overrule London Mayor Sadiq Khan's ULEZ scheme?
Tamara Cohen: The ULEZ scheme is already in place in central London and its growth to the outer boroughs, which is because of occur on the finish of August, is topic to a High Court problem by 5 London councils together with Hillingdon - the place the Uxbridge by-election happened.
We might hear the consequence later in the summertime.
Labour's candidate in Uxbridge referred to as for a delay within the implementation and a extra in depth scrappage scheme, not ditching it altogether.
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