Britain's main opposition leader has launched his election campaign, painting himself as a populist outsider who will overturn a "rigged" political and economic system.

Labour Party chief Jeremy Corbyn says Britain's June 8 election is "the establishment vs. the people."

Labour is trailing Prime Minister Theresa May's Conservatives in opinion polls, and many within the party think the socialist Corbyn is too left-wing to connect with voters.

But Corbyn echoed anti-establishment sentiment that has upended politics from the United States to France. He said in a speech Thursday that the old rules drawn up by political and economic elites no longer apply.

Corbyn said: "I don't play by their rules, and if a Labour government is elected on the 8th of June I won't play by their rules either."