Jeremy Corbyn handed boost as Labour edges Conservatives in latest poll

Labour has narrowly pulled ahead of the Conservatives for the first time since Jeremy Corbyn became leader of the Opposition in September 2015 with the largest mandate ever won by a party leader. The YouGov poll was held after Chancellor George Osborne's budget on 16 March, just days after Labour drew level with the Tories, according to an ICM survey.

The latest poll saw Labour take the edge with 34% of the vote while the Conservatives fell behind by one point. Ukip took a 16% share while the Lib Dems trailed further behind on 6%.

In a significant blow for Osborne, more people branded yesterday's Budget unfair than fair – by a 10-point margin – for the first time since the Omnishambles of 2012. His previous budgets have generally been considered fair by the public.

Much public anger was directed at the decision to slash the personal independence payment, with only 13% of people saying it was a good idea. The move to force all schools to become academies was similarly unpopular, drawing support from just 14% of voters.

The poll revealed that 44% of people still think that spending cuts are necessary, compared to 33% who think they are not. But Osborne's Budget is just one contributing factor behind the Tory slip in the polls.

The party continues to be plagued by infighting over the upcoming referendum on Britain's EU membership on 23 June. YouGov director Anthony Wells said: "It is reasonable to conclude that Euro squabbles are hurting the party's image."

Wells added: "People were understandably wary of reading too much into one poll (the ICM poll), but we now have two polls both showing Labour and the Conservatives neck-and-neck, suggesting something is genuinely afoot."

In a blow for the Conservative party – which has repeatedly presented itself as the only party which can be trusted with managing the economy – more than half of the respondents (51%) think the government has been handling the economy badly.