An attempt by Wall Street at the opening to recoup the week's losses fizzled out, weighing on European stocks which also gave up their earlier gains.

The pound had a rollercoaster day as Prime Minister Theresa May defended her divorce deal with the EU before rowdy lawmakers and tried to win the backing of her splintered cabinet.

But reports that May was to make a statement shortly after the markets' close pushed the British currency firmly into positive territory.

"Markets have rallied on news that a Brexit deal has been reached but there's still a long way to go," said Chris Turner, an analyst at ING.

"We still think 'no deal' will be avoided in the end," he said.