A summit of 28 European Union leaders planned for 12 July has been cancelled, as crisis Eurozone talks over a third bailout deal for Greece continue.

A separate meeting of 19 Eurozone leaders will convene on 12 July at 2pm GMT but the full European Council with all 28 member states has been cancelled.

Announcing the news, European Council President Donald Tusk tweeted: "I have cancelled EUCO (the European Union summit) today."

Eurozone finance ministers are calling for more austerity measures from near-insolvent Greece in return for a third debt relief package, as last-ditch negotiations in Brussels broke up without agreement on 11 July.

"Very difficult" marathon talks between the 18 eurozone ministers and Greek Finance Minister Euclid Tsakalotos went on for more than eight hours before adjourning at midnight, with officials struggling to make headway towards agreeing on a package worth up to €74bn (£53.2m, $82.5bn) for Athens.

"We have had an in-depth discussion of the Greek proposals, the issue of credibility and trust was discussed and also of course financial issues involved, but we haven't concluded our discussions," Eurogroup leader Jeroen Dijsselbloem told reporters following the meeting.

"It is still very difficult but work is in progress."

Greece Prime Minister Alexis Tsipras had proposed €13bn (£9.3m) of cuts to the country's budget in return for a three-year bailout deal.

But Eurozone ministers say the cuts do not go far enough and demand further commitments from Greece on product market liberalisation, labour laws, privatisation, government reform and more defence cuts, along with a pledge to pass key laws next week.

Without a deal, it is feared Greece could crash out of the euro.