The two main political parties are showcasing starkly different visions for the world's fifth largest economy ahead of the Dec. 12 election. The Conservatives are promising to deliver Brexit while Labour says it wants to be the most radical socialist government in British history.

Labour said almost a third of Britain's 151 billionaires have donated more than 50 million pounds ($64.8 million) to the Conservatives since 2005 in return for tax breaks for the wealthy and corporations worth 100 billion pounds.

John McDonnell, the party's finance minister-in-waiting, will say in a speech he wants to "rewrite the rules of our economy", casting the election as a chance to overthrow a system where billionaires can buy access to power.

"No one needs or deserves to have that much money, it is obscene," McDonnell will say, according to excepts of his speech. "It is also obscene that these billionaires are buying access and tax breaks to Boris Johnson's Conservative Party."

Labour's core message -- a pledge to redistribute wealth to the many and not the few -- was a theme it used in the 2017 election, when the party confounded the polls to deprive then Prime Minister Theresa May of her parliamentary majority.