A senior Labour frontbencher has placed a bet on live television that Rishi Sunak will call a general election in May. Jonathan Ashworth, a shadow Cabinet Office minister, put his money where his mouth was on Tuesday when he agreed a £10 bet with the Sky News presenter Kay Burley that the election would be held in May. They shook hands, with Ashworth suggesting that the money should go to a charity for the children of alcoholics. “I think everything the Conservatives are doing in terms of both their advertising on social media and the political positioning suggests to me that May is their preferred choice,” Ashworth told Times Radio. “I think it’s going to be May. And I think Rishi Sunak now needs to name the date because there’s so much uncertainty. And businesses, companies seeking to invest in the UK economy need certainty, which is why I’m challenging Rishi Sunak to offer that certainty and confirm a May election.” The prime minister said in January that he was working on the assumption that he would call a general election “in the second half of this year”. However, the Guardian understands that Labour has been readying its plans to put the party on a battle footing for a poll sooner than the end of the year and that frontbenchers received a presentation by strategists last week on the possibility of a May election. Leaving the election until later in the year holds out the possibility of the Conservatives being able to garner some support if interest rates fall further. However, the argument for calling on in May is premised on the notion that things can only get worse for the Conservatives if they wait. The party’s support has fallen to the lowest level in more than four decades, according to an Ipsos poll, which put support for the Tories at 20% at the end of February, down seven percentage points in a month. Labour was on 47%. Greg Hands, the minister for London and minister of state for trade policy, replied “no” when asked on Times Radio on Tuesday if he believed there was a chance of an election being called in May. The former chancellor George Osborne has said that Sunak is planning a general election on 14 November, as the prime minister seeks to maximise the amount of time he has to recover the Conservatives’ poll deficit. Speaking on Political Currency, the podcast he hosts with the former Labour cabinet minister Ed Balls, Osborne said he had been told Sunak’s team was working towards the date in mid-November as the target for an election. “My working assumption is that we will have a general election in the second half of this year,” Sunak said in January, using a phrase that might give him some room to change his mind should circumstances change. However, he has since been sheepish when quizzed by broadcasters to name the date.