French President Francois Hollande on Monday urged a quick restart of talks to save Greece from financial disaster after negotiations in Brussels collapsed at the weekend.

"We now have extremely tight deadlines. We are getting into a period which could be turbulent if no agreement is found. This message is for Greece. It should not wait and should restart discussions with the institutions," Hollande told reporters.

"Let's not waste time. Let's restart talks as quickly as possible," Hollande added as he visited the Paris Air Show at Le Bourget outside Paris.