Corbyn's soaring popularity shows the risks facing the DUP

This must be one of the most dramatic turnarounds in public perceptions in political history – the prime minister began the election with a plus-10 rating (ie 10% more people had a favourable rating than did not). The Labour leader was a miserable minus-42 when campaigning began.

According to YouGov Mrs May has now plunged to minus-34, the level Mr Corbyn was at last November, while he has soared zero (as many people approve of him as do not).

This is further proof that Mr Corbyn could become prime minister if there is a fresh election, something that became clear on Friday when it emerged that Labour had won 40% of the vote, and was within striking distance of the Tories.

A Corbyn premiership would be bad for Britain, because he would run up vast government debts with his huge spending commitments, and he would be unreliable on crucial issues such as national security. But with his sympathy for Sinn Fein, even at the height of the IRA murder campaign, Northern Ireland could be worst hit if he made it to Downing Street.

The DUP should work carefully with the Conservatives to avoid another general election in the short term.

There are reports that the Treasury has concerns at some DUP demands. While it of course makes sense to use this new influence to seek funds for Northern Ireland, particularly for infrastructure that can command cross-community support such as the completion of the A6 Belfast to Londonderry dual carriageway, it is to be hoped that the DUP will not seek to row back on matters such as welfare reform, that are important in making the Northern Ireland economy a more productive one, that is less reliant on benefits than it has been. Also that the party will not alienate powerful Tories by appealing to the populist instincts in Great Britain, that won Mr Corbyn support for his irresponsible plans, and blocking key nationwide fiscal reform at this time of ever-rising UK national debt.