The UK's EU commissioner has announced that he is to stand down from the top role in reaction to Britain voting to split from the political and economic union in the 23 June referendum. Lord Jonathan Hill, an ally of David Cameron who also campaigned for a Remain vote, declared "what is done cannot be undone" in his resignation statement.

"Like many people here and in the UK, I am obviously very disappointed about the result of the referendum," he said. "I wanted it to end differently and had hoped that Britain would want to play a role in arguing for an outward-looking, flexible, competitive, free trade Europe.

"But the British people took a different decision, and that is the way that democracy works. As we move to a new phase, I don't believe it is right that I should carry on as the British Commissioner as though nothing had happened.

"In line with what I discussed with the President of the Commission [Jean-Claude Juncker] some weeks ago, I have therefore told him that I shall stand down. At the same time, there needs to be an orderly handover, so I have said that I will work with him to make sure that happens in the weeks ahead."

Hill also praised Juncker, who intends to make European Commission vice-president Valdis Dombrovskis take over Hill's financial services portfolio, for the opportunity to "help support jobs and growth in Europe". He added: "I came to Brussels as someone who had campaigned against Britain joining the euro and who was sceptical about Europe.

"I will leave it certain that, despite its frustrations, our membership was good for our place in the world and good for our economy. But what is done cannot be undone and now we have to get on with making our new relationship with Europe work as well as possible."

'I am a winner. I can win this'

The comments come after Cameron announced his own intention to resign as prime minister in the wake of the EU referendum result. The Conservative leader was not invited to talks between the EU's founding members in Berlin on 25 June. The states, including Germany, Italy and France, have urged the UK to exit quickly from the 28-nation-bloc.

"This process should get underway as soon as possible so that we are not left in limbo but rather can concentrate on the future of Europe," Reuters reported Frank-Walter Steinmeier, the German foreign minister, saying.

But Cameron decided not to trigger Article 50 of the Lisbon Treaty immediately after the UK backed a Leave vote, which would have triggered a two-year timetable for negotiations with Brussels. The prime minister said he wanted his successor, who he wants to be elected by October, to start the talks.

Cameron's political legacy has been left tarnished by the Brexit result. He played a prominent role in the unsuccessful Remain campaign and called the referendum after committing to it in the Tories' 2015 general election manifesto. "I am a winner. I can win this," he reportedly told European leaders in December, The Times reported.