Brexit Turmoil Grips UK Amid Leadership Squabbles

— -- British politicians experienced a weekly address in Parliament like no other, with a prime minister who is stepping down and an opposition leader whose own party is trying to force him out.

A majority of Labour Party members of Parliament (MPs) have backed a motion of no-confidence in their leader Jeremy Corbyn, but he is refusing to step down.

"For heaven's sake, man, go!" Prime Minister David Cameron said addressing the House of Commons.

Nominations for the Conservative Party leadership open today, with Boris Johnson and Theresa May expected to throw their hats in, as well as Stephen Crabb, Nicky Morgan and Jeremy Hunt.

"I was given lots of advice on becoming prime minister, one of them was not to go to a party with Silvio Berlusconi and that's one bit of advice I took and stuck to," Cameron joked.

As the political turmoil continued, U.K. markets rallied after days of volatility. London's FTSE 100 Index closed at at 6360.06, above the 6338 level on the day before the referendum results were announced.

MPs who campaigned for Brexit were booed in Parliament as one of their representatives tried to address the floor.

"We on the Leave side should recognize that although we won, it was a narrow mandate with plenty of decent, patriotic people voting for Remain," Douglas Carswell, a member of the U.K. Independence Party representing Clacton, managed to say after Speaker John Bercow intervened.

"The honourable gentleman will be heard and it's about us and this place that he will be heard," Bercow hammered.

Meanwhile, Scottish First Minister Nicola Sturgeon held a series of meetings in Brussels to lobby for Scotland to remain in the EU.

Speaking ahead of a meeting with Sturgeon, Jean-Claude Juncker, the European Commission president, said he would "listen" to her case.

"I will listen carefully to what the first minister will tell me, but we don’t have the intention -- neither [European Council President] Donald [Tusk] nor myself -- to interfere in the British process. That is not our duty and not my job," Juncker said.

Juncker also made clear that there can be "no single market a la carte" for the U.K. and that anyone wanting access to the EU's internal market had to adhere to strict criteria "without exception."