Larry Sanders, the brother of the US Senator Bernie Sanders, has been selected by the Green Party to contest a by-election in David Cameron’s former constituency.

Mr Sanders, who will fight the Witney by-election for the Greens, announced his decision to run one week after the former Prime Minister announced he would resign as an MP following his fatal defeat at the European Union referendum.

The Sanders brothers were born in Brooklyn before Larry moved to Britain in the 1960s after studying at Harvard Law School. It is not the first time Mr Sanders, however, has run for a parliamentary seat – at the 2015 general election he secured 4.4 per cent of the vote in the nearby Oxford West and Abingdon seat.

Mr Sanders, the Greens’ health spokesperson who has lived in Oxford since 1969, will use the by-election to fight against NHS privatisation and campaign for proportional representation after he was selected by the West Oxfordshire Greens. According to the Greens he has served a local councillor and spent eight years as leader of the Oxfordshire council Green group.

“The major political parties are in disarray,” Mr Sanders said in a statement. “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. The Green Party has pledged to make Britain a fairer and less divided nation.

“We need to show that we don’t want Britain to be the most unequal country in Europe. We don’t want unmet health needs to increase when we already have too few doctors, nurses, and hospital beds.

“We don’t want the Government to impose unworkable contracts on 50,000 precious doctors, when it is clear that the supposed reason for the contract, a seven day hospital service, can’t be done at present funding.

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

Bernie Sanders campaigns with Hillary Clinton Show all 15 1 /15 Bernie Sanders campaigns with Hillary Clinton Bernie Sanders campaigns with Hillary Clinton Democratic presidential candidate Hillary Clinton, followed by Sen. Bernie Sanders, I-Vt. arrives for a rally in Portsmouth, N.H., Tuesday, July 12, 2016. Andrew Harnik/AP Bernie Sanders campaigns with Hillary Clinton A woman holds a sign at an event where Bernie Sanders will appear with Hillary Clinton at Portsmouth High School July 12, 2016 in Portsmouth, New Hampshire. Sanders and Clinton are expected to show unity within the party and a forwarding of their agendas. Darren McCollester/Getty Bernie Sanders campaigns with Hillary Clinton Cerys Coffey, 5, of North Hampton, Massachusetts, walks along a line of supporters waiting to get into a campaign event with Democratic U.S. presidential candidates Hillary Clinton and Senator Bernie Sanders in Portsmouth, New Hampshire, U.S., July 12, 2016. Mary Schwalm/Reuters Bernie Sanders campaigns with Hillary Clinton Democratic U.S. presidential candidate Hillary Clinton and Sen. Bernie Sanders stand together during a campaign rally where Sanders endorsed Clinton in Portsmouth, New Hampshire, U.S., July 12, 2016. Brian Snyder/Reuters Bernie Sanders campaigns with Hillary Clinton Democratic U.S. presidential candidate Hillary Clinton and Sen. Bernie Sanders greet supporters during a campaign rally where Sanders endorsed Clinton in Portsmouth, New Hampshire, U.S., July 12, 2016. Brian Snyder/Reuters Bernie Sanders campaigns with Hillary Clinton Democratic U.S. presidential candidate Hillary Clinton speaks as Senator Bernie Sanders looks on after he endorsed her during a campaign rally in Portsmouth, New Hampshire, U.S., July 12, 2016. Brian Snyder/Reuters Bernie Sanders campaigns with Hillary Clinton Democratic U.S. presidential candidate Hillary Clinton (R) looks on as Senator Bernie Sanders endorses her during a campaign rally in Portsmouth, New Hampshire, U.S., July 12, 2016. Brian Snyder/Reuters Bernie Sanders campaigns with Hillary Clinton Democratic U.S. presidential candidate Hillary Clinton looks on as Senator Bernie Sanders endorses her during a campaign rally in Portsmouth, New Hampshire, U.S., July 12, 2016. Brian Snyder/Reuters Bernie Sanders campaigns with Hillary Clinton Democratic presidential candidate Hillary Clinton, followed by Sen. Bernie Sanders, I-Vt., arrives for a rally in Portsmouth, N.H., Tuesday, July 12, 2016, where Sanders endorsed Clinton for president. Andrew Harnik/AP Bernie Sanders campaigns with Hillary Clinton Sen. Bernie Sanders, I-Vt. waves as he a Democratic presidential candidate Hillary Clinton arrive for a rally in Portsmouth, N.H., Tuesday, July 12, 2016. Andrew Harnik/AP Bernie Sanders campaigns with Hillary Clinton People hold signs outside an event where Bernie Sanders will appear with Hillary Clinton at Portsmouth High School July 12, 2016 in Portsmouth, New Hampshire. Sanders and Clinton are expected to show unity within the party and a forwarding of their agendas. Darren McCollester/Getty Bernie Sanders campaigns with Hillary Clinton Supporters for Democratic presidential candidates Hillary Clinton and Sen. Bernie Sanders, I-Vt. cheer before a rally in Portsmouth, N.H., Tuesday, July 12, 2016, prior to the arrival of Clinton and Sanders. Sanders is poised to offer his long-awaited endorsement of Clinton, hoping to transfer the energy of his supporters into the party's fight against Republican Donald Trump. Andrew Harnik/AP Bernie Sanders campaigns with Hillary Clinton Supporters of Democratic presidential candidate Hillary Clinton sing the national anthem in Portsmouth, N.H., Tuesday, July 12, 2016, prior to a rally with Democratic presidential candidates Hillary Clinton and Sen. Bernie Sanders, I-Vt. Sanders is poised to offer his long-awaited endorsement of Democratic rival Hillary Clinton, hoping to transfer the energy of his supporters into the party's fight against Republican Donald Trump. Andrew Harnik/AP Bernie Sanders campaigns with Hillary Clinton Supporters of Democratic presidential candidate Hillary Clinton sing the national anthem in Portsmouth, N.H., Tuesday, July 12, 2016, prior to a rally with Democratic presidential candidates Hillary Clinton and Sen. Bernie Sanders, I-Vt. Sanders is poised to offer his long-awaited endorsement of Democratic rival Hillary Clinton, hoping to transfer the energy of his supporters into the party's fight against Republican Donald Trump. Andrew Harnik/AP Bernie Sanders campaigns with Hillary Clinton A woman holds poster for Democratic presidential candidate Hillary Clinton during a rally in Portsmouth, N.H., Tuesday, July 12, 2016, where Sen. Bernie Sanders, I-Vt. endorsed her for president. Andrew Harnik/AP

However, unless Mr Sanders manages to inject a degree of left-wing activism into the conservative stronghold of Witney, it is unlikely he’ll be in the House of Commons in four weeks’ time. At the 2015 general election Mr Cameron, albeit the Prime Minister at the time, secured 60 per cent of the vote while the Greens trailed behind in fifth place with a five per cent share.

David Cameron’s heir in the constituency was also announced on Thursday as 37-year-old Robert Courts – a “devoted champion” of the area, according to the party. Commenting on his selection, Robert Courts, added: “I am hugely honoured to have been selected as the Conservative candidate for Witney and West Oxfordshire.