It will be "impossible" for Brexit talks to result in a deal that gives Britons more rights than others outside the EU, Italy's PM has told the BBC, the news agency reports.

Matteo Renzi warned that leaving the EU would be a "very difficult process" - but the problems could be solved only after the UK began the exit procedure.

He said the Brexit vote had been "a bad decision" but had to be respected.

Meanwhile a German business leader said a so-called "hard" Brexit, rather than a "fudge", was the only option.

Following the UK's vote to leave the EU in June's referendum, attention has focused on the government's likely demands in Brexit negotiations.

Renzi said he had been shocked and saddened by the referendum result, but repeated May's vow that "Brexit is Brexit", saying democracy had to be respected.

Asked about whether there could be "flexibility" over EU rules on freedom of movement and access to the single-market, he said "I think this is a very interesting debate, because this debate will be a debate about the concept of rules in the EU."

But he said that debate could only begin once the UK had triggered article 50 - the official procedure for it to start leaving the EU - and he warned: "It will be impossible to give to British people more rights than other people outside the EU."