London (CNN) Prime Minister Theresa May looks like she's lost her government majority in the UK election, according to the official exit poll. A hung parliament -- where there is no overall winner -- would make a huge difference to Brexit. Here's what might happen, depending on the final results:

Conservatives short of a majority -- hung parliament:

A disaster for the PM, because she has thrown away the first Conservative majority government for 18 years after just two.

A hung parliament would be a disaster for May.

Even if the Tories are the largest party with the most number of seats and will therefore have the first chance to form a government, she will find it difficult to go into coalition with a smaller party like the Liberal Democrats, who are fundamentally opposed to Brexit.

There is no chance of her doing a deal with Labour or the Scottish National Party, who are on opposite sides of the political divide to the Conservatives. She might be able to form a coalition with the Northern Ireland party the DUP, who are in favor of Brexit, but they are themselves set to lose seats on June 8 and the numbers might not be enough for an overall majority. In any case, some Conservative MPs will be so furious that power has been lost after an unnecessary election and will demand she steps down.

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