Greece has been warned it has "one last chance" to agree a deal on its debt crisis or risk crashing out of the euro.

 

But the UK Government warned that Greece's economic problems could catch up with it before any agreement with its creditors can be struck.

France and Germany sounded a more upbeat note as they told Greece it had to come up with a serious proposal with which to restart financial aid talks.

The warnings come ahead of a crunch meeting of Eurozone leaders later today in the wake of Greece's defiant No vote against the latest aid package in a referendum on Sunday.

"The door is open for discussion," the French President François Hollande said.

"It's now up to the government of Alexis Tsipras to offer serious, credible proposals so that this will can be turned into a programme which gives a long-term perspective.

"Because Greece needs a long-term perspective in the eurozone."

Earlier, the Chancellor George Osborne had warned politicians attempting to strike a deal that time was running out for Greece's banks.

A Treasury source added that "no one knows" how much money is left in Greek institutions.

Mr Osborne also pledged that the government would do "whatever is necessary" to protect the UK's economy against the fallout from Greece.

Stocks markets across Europe fell, although there were were few signs of panic from traders.

While the FTSE100 dropped by less than one per cent, however, banks and oil companies saw their share price hit with Royal Bank of Scotland falling more than 3.5 per cent and BP and Royal Dutch Shell also both down.

More consular staff are being posted to Greek islands to help holidaymakers deal with the crisis.

The Foreign Office has also highlighted advice that holidaymakers with long-term conditions should carry medication to Greece with them, amid fears the country may start to experience prescription drug shortages.

Businesses were also told to ring a government helpline if they had problem getting paid by Greek firms.

Ministers also announced that officials had spoken to 2,000 Britons in Greece about how to move payments from the UK into non-Greek bank accounts.

The Tsipras' government in Greece has long sought some debt relief from other eurozone countries including Germany.

In a signal that Athens is keen to restart talks, the country's combative finance minister, Yanis Varoufakis, resigned just hours after the referendum result, apparently under pressure from other eurozone finance ministers.

Tsipras himself said that he would "go back to the negotiating table", but added that the arguing the result meant a deal on debt relief should now be on the table.

But EU officials warned it would be hard to offer Greece easier terms, in part because the country has slid back into recession since Tsipras' Syriza party won power in January.

The UK Government indicated that it would expect to be included if there was a Greek exit.

"Issues that affect the 28 EU countries affect all 28, " a source said.

Mr Osborne told MPS he had spoken to IMF managing director Christine Lagarde and eurogroup president Jeroen Dijsselbloem.

"There is considerable uncertainty about what happens next," he said.

"We need to be realistic: the prospect of a happy resolution to this crisis is, sadly, diminishing."

"This is a critical moment in the economic crisis in Greece. No one should be under any illusions: the situation risks going from bad for worse; Britain will be affected the longer the Greek crisis lasts and the worse it gets. There is no easy way out, but even at the 11th hour we urge the eurozone leaders and Greece to find a sustainable solution."

A government source added: "There is one last chance for a solution".

Earlier Prime Minister David Cameron chaired a meeting on the impact of the Greek vote on the UK.

The SNP's Stewart Hosie said that most people recognised that irrespective of the outcome of the referendum "negotiations and difficult decisions would still have to be undertaken by both Greece and its creditors".

He called on the Chancellor to try to persuade his finance minister counterparts in the EU and colleagues in the IMF that they should "respect the outcome of the referendum, stay calm and return to the negotiating table to find a long-term sustainable solution to Greece's problems. That is in all our best interests".