A “very optimistic” Jeremy Corbyn has insisted that a Labour Party under his leadership would unite, “go for it” and win a snap general election if Theresa May dared to call one.

His bold assertion came in a week when two opinion polls gave the Conservatives leads over Labour of 16 points and 10 points while one snapshot suggested 29 per cent of Labour voters, some 2.7 million people, preferred the Tory leader as Prime Minister to Mr Corbyn. Mrs May is coming under increased Tory pressure to consider going to the country either this autumn or next spring.

In a newspaper interview, the Labour leader also lashed out at the UK media, saying much of it had “systematically undermined” his leadership with the vast majority of the Press either uninformed about his views or “totally biased against me; in some cases ludicrously so”.

The London MP, who is due to attend a leadership campaign rally in Yorkshire tonight, criticised some of his parliamentary colleagues, saying the Tories had had “a field day” because of Labour’s internal divisions and he appealed to his MPs to “think carefully,” pointing out how the official opposition had defeated the Conservative Government on a number of issues such as cuts to working tax credits, had won four parliamentary by-elections and had recruited 300,000 more party members.

Ahead of the first head-to-head debate with his leadership rival Owen Smith next week, Mr Corbyn was asked by The Guardian what Labour stood for.

He replied: an economy that did not cut expenditure but invested to give opportunities to everyone; a welfare system that supported and did not punish people with disabilities; a national health service for all without any charges, and a foreign policy, which was based on human rights and democracy.

Mr Corbyn emphasised how his policies were “more radical” than those of his predecessor Ed Miliband; from the renationalisation of the railways and the Royal Mail to a real Living Wage. “We are looking at the TUC figure of £10 an hour,” explained the MP for Islington. At present, it is £7.20 for people over 25.

A large part of the interview focused on the Labour leader’s strained relationship with the media.

“There is a systematic undermining by a lot of the house media, around the House of Commons; the Lobby,” said Mr Corbyn.

He referred to analysis, which he said, showed that “83 per cent of all print media is either uninformative of my views or totally biased against me and in some cases ludicrously so. Is it a cause of concern? It’s a cause of irritation; that it’s very hard to get a fair hearing in most of the media but we have developed a very large social media following, which does reach out predominantly but not exclusively to a younger audience.”

He went on: “A lot of newspapers start with their opinion of me, continue for the rest of the article and then conclude with saying what a bad person I am. It’s not very nice; it’s not fair.”

But Mr Corbyn noted how the regional media were very different. “They give you more opportunity and more time and are actually more interested in what you have to say.”

Asked about Labour being wiped out if the Prime Minister called an early general election, the Labour leader said he viewed it “the other way round,” saying his party would “call it out” on housing, jobs, the environment and education.

“On do you want to be in a society that is more unequal, do you want to be to be bargain-basement Britain on the edge of Europe, cutting corporate taxation, having very low wages, having grotesque inequalities of wealth? Or do you want to be a high-wage, high-investment economy, that actually does provide decent chances and opportunities for all?

“Do you want Labour with its principles of the unity of the entire community or do you want the divisiveness of the Tories; that’s the message,” he declared.

Asked if he could win a snap election, Mr Corbyn replied: “We’re going to go for it and win it…It will be a united Labour Party around those principles.”