Larry Sanders at home in his kitchen in Oxford, England, Monday, Feb. 15, 2016. AP Photo/Kirsty Wigglesworth The Green Party has selected Larry Sanders, brother of US senator Bernie Sanders, as its candidate for a by-election in David Cameron's constituency.

Last week, the former Prime Minister announced that he would resign as the MP for Witney, Oxfordshire, following his defeat in the EU referendum.

Larry Sanders, 82, was born in Brooklyn, New York, but emigrated to the United Kingdom in the 1960s. Since then he has worked as an academic and local councillor. Currently, he is the Green Party's health spokesman.

He intends to campaign on a pledge to fight NHS privatisation, and said that the major political parties are in "disarray."

"The policies of the last 30 years, shifting resources and power from the majority to the richest, culminated in the illegality and greed which crashed the economy in 2008," he said in a statement sent to Business Insider.

"This is a rich, capable and decent country. We can do better."

Winning the by-election will be a difficult job: the Greens won just 5.1% of the vote in Witney at the 2015 general election. In the same election, Sanders stood for the nearby seat of Oxford West and Abingdon and secured 4.4% of the vote.

His brother Bernie, who ran a high-profile campaign against Hilary Clinton to become the Democratic presidential candidate, credits his own political ideas to his older brother.

"We didn't have a whole lot of books in the house and it was my brother who actually introduced me to a lot of my ideas so I hope he does very well in his race for parliament in the UK," Sanders told The Daily Telegraph before the 2015 general election.