London CNN  — 

British Prime Minister Theresa May has failed to win a parliamentary majority in the UK election, leaving the country with what’s known as a “hung parliament.”

May’s Conservative Party needed to win 326 of 650 seats in the UK parliament to govern with a full majority. Instead, now she’s being forced to consider teaming up with a minor party.

So what exactly is a hung parliament?

The expression comes from the term “hung jury,” when jurors cannot decide on a verdict and a retrial is needed.

But in UK elections this result does not automatically trigger another election. Instead, the party with the largest number of seats – in this case, it looks like the Conservatives – will attempt to form a coalition government with one of the smaller parties.

The second-largest party – which would be Labour – can also start parallel talks to try to form a coalition of its own in an effort to reach the magic number of 326. If no-one can reach a deal, a party could try form a minority government, but it would struggle to pass laws in parliament.

There will be a sense of urgency to the coalition talks to form a new British government because the Brexit clock is ticking: formal negotiations between the British government and the EU are due to start on June 19 – just 10 days away. Without a stable government in place, it will be impossible to start Brexit talks and they will have to be delayed.

If the hung parliament is confirmed, what happens next?

If, as looks likely, the Conservatives end up with the largest number of seats, they get to go first in trying to form a government by going into coalition with other parties. But before the talks can start, there will be widespread anger across the Conservative Party that she has thrown away a majority for the sake of an unnecessary early election.

So there will be moves against her and MPs could call on her to stand down. However, many Conservatives will not want to appear disunited when there is already uncertainty about what the new government will look like, which could blunt any possible challenge.

The first 24 hours: staking a claim for power

Putting aside any demands for May to stand down, the party with the largest number of seats must reach out to other parties to strike a deal to share power.

This could be undertaken in a formal coalition or an informal arrangement known as confidence and supply, where a smaller party agrees to back the larger partner in crucial votes in return for policies but does not take ministerial seats.

If the result is tight, or if the popular vote gives a different winner to the tally of seats, as much will depend on fixing a narrative in the early stages as straightforward math. Which leader can assert authority over the way the results have fallen, and who can stake a claim to form a government?

This could see separate statements by May and Labour leader Jeremy Corbyn to the media in the early hours of Friday each declaring they have a moral mandate to lead the country.

Over the weekend: getting down to real talks

The last time a UK election resulted in a hung parliament was 2010. The Conservatives were the largest party but the sitting Labour prime minister, Gordon Brown, stayed in Downing Street while backroom negotiations got under way over the Saturday and Sunday following polling day on the Thursday.

This is when the real action takes place: the Conservatives, as the largest party, will meet with other parties to see if they can strike a deal. In 2010, that was the Liberal Democrats.

But that was when the Lib Dems could have gone either way – with David Cameron’s Conservatives, to whom they were more sympathetic, or Labour. This time, the Lib Dems are more left-wing and are vociferously anti-Brexit, so are more likely to side with Labour.

The Conservatives can more realistically hope for the backing of one or both of the unionist parties in Northern Ireland, the DUP and UUP, who are supportive of May’s Brexit position. However, between them they currently have just 10 MPs and are predicted to lose some seats, making May’s chances of achieving a working majority, even in a coalition, appear slim.

Could Labour’s Jeremy Corbyn be Prime Minister?

It is likely that, while these talks are going on, Labour will hold parallel negotiations with other broadly left-wing parties like the Lib Dems, Greens, the Scottish National Party and the SDLP from Northern Ireland.

Britain's main opposition Labour Party leader Jeremy Corbyn leaves a polling station after casting his vote.

Even if Labour have fewer seats than the Conservatives, they have more choice in prospective coalition partners, so could be more likely to form a “progressive alliance”. The LibDems and SNP, who are both more anti-Brexit than Labour, would demand key concessions from Corbyn on EU membership as conditions for power-sharing.

The SNP has said it will not enter a formal coalition with Labour but could support them through confidence and supply.

Monday morning: time to decide

A make or break situation for May might be reached over the weekend. There is no strict timetable for coalition talks to follow, and in 2010, an agreement was not reached until the following Tuesday, five days on from the election.

But if May has not secured a deal with another party by Monday morning, there will be pressure on her to call off the talks, particularly if Labour can show it can form a coalition with other parties to form a working majority and send Corbyn into Downing Street as Prime Minister.

Stalemate?

If the seats tally is really tight, it’s possible that neither of the main parties, Conservatives or Labour, can form a coalition that has an overall majority. At that point, one of the leaders would have to show they could form a minority government that had the support of other parties.

Given Brexit talks are due to start on June 19, a weak minority government with no real mandate would undermine Britain’s position in negotiations, leaving open the possibility of another election later this year, as happened in the UK in 1974. But this is a scenario wished by almost no one in Westminster.