Two senior Conservative politicians warned Britain's prime-minister-in-waiting Theresa May that she will need to heal divisions in the party, as calls grew on Tuesday for her to move faster in opening Brexit negotiations.
Veteran lawmaker Ken Clarke said May will have to "balance the party" after the Brexit campaign exposed its "warring wings." He urged her to open talks on Brexit with EU officials in the next few weeks.
"She has a real problem bringing the warring wings of the party together," Clarke told BBC Radio 4. "Our majority [in parliament] isn't big enough to get the real headbangers together."
May attended Prime Minister David Cameron's final cabinet meeting on Tuesday, before Cameron hands over to her after seeking Queen Elizabeth II's approval on Wednesday.
May had advocated waiting until the end of this year to invoke Article 50 of the Lisbon Treaty, which sets the rules for a nation leaving the EU, despite a clamour from many British and EU politicians to move more quickly.
Writing on The Guardian's website on Tuesday, European Parliament President Martin Schulz said he expects Britain to open negotiations on its withdrawal from the European Union "after the summer."
"Now that the country has full clarity on its new prime minister, after the summer I expect the British government to notify its intention to withdraw the UK from the EU," Schulz said.
"Negotiations must be concluded swiftly," he said. "The world will not sit idly by as Europeans navel-gaze."
Some British politicians have argued that Britain could negotiate a deal to say in the single market without having to accept EU rules on free movement of people.
But Schulz warned Britain that the European single market "entails four freedoms (capital, goods, services, persons) and not three, or three and a half."
Speaking in Brussels earlier Tuesday, EU Economy Commissioner Pierre Moscovici said he hoped the faster than expected Conservative Party election for Cameron's successor meant it was "possible that the process of the discussions with the EU also accelerates."
Clarke said prolonged economic uncertainty could damage the economy in Britain and the wider European Union.
May and her new cabinet should "sort out the outlines of our economic and trading relationships as quickly as possible," he told the BBC, adding that informal discussions were "not going to get very far."
"We can't just drift on with uncertainty," he said. "They've got to get a team together to negotiate, work out what they want."
Much attention will focus on what roles, if any, May hands prominent Brexit campaigners Andrea Leadsom, Boris Johnson, Michael Gove, Chris Grayling and Liam Fox in her new cabinet, amid speculation that one of those five could be given a new post of Brexit minister.
Veteran right-wing Conservative Norman Tebbit claimed May's final challenger, Leadsom, who withdrew from the race on Monday, had suffered an "intense smear campaign run by supporters of May."
The victory of May, who backed Cameron's Remain in the referendum campaign, could leave Conservatives who wanted a pro-Brexit leader "bitterly disappointed" and pushing them towards the anti-EU UK Independence Party, Tebbit wrote Tuesday's Telegraph.