Rishi Sunak will call a general election for 4 July, Sky News understands.
The surprise move comes after days of rumours the prime minister could go to the country earlier than previously thought.
Follow the latest politics news live – general election to be confirmed
Mr Sunak has been saying for months an election would happen in the “second half of the year” but had refused to set a date.
The assumption in Westminster was that he would call the vote in the autumn, to give his party more time to make up ground against Labour.
Sir Keir Starmer’s party are ahead by about 20 points after he set about transforming Labour following its historic defeat in 2019.
Deputy PM Oliver Dowden in particular has been pushing for a summer election, according to Sky News’ political editor Beth Rigby.
She said: “On the back these good inflation figures, the International Monetary Fund upgrading the growth forecasts, the UK coming out of recession, the prime minister looks like he is going to go in the summer.”
Under parliamentary rules, there has to be 25 working days between the dissolution of parliament – at the request of the prime minister – and voters going to the polls.
Read more: The current state of the parties in the polls
As general elections have to be held every five years, the final day a vote could have taken place was 28 January 2025.
However, the Conservatives in 2019 restored the prime minister’s power to call an election at a time of their choosing within that five years.
The last general election was held in 2019, when Boris Johnson won the Conservatives a landslide over Jeremy Corbyn’s Labour Party.
Since then, there have been two more prime ministers, Liz Truss and Mr Sunak, and the Conservatives’ 80-seat majority has been reduced.
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