BRUSSELS (Reuters) - All 28 national leaders of the European Union will meet in Brussels on Sunday for a summit that could sign off on a new bailout deal for Greece, Italian Prime Minister Matteo Renzi said on Tuesday.

"We can achieve an agreement on Sunday," he said after leaders of the 19 countries in the euro zone held an emergency summit. "I'm not pessimistic."

He said it was now up to Greece to come up with proposals.

(Reporting by Francesco Guarascio; Editing by Alastair Macdonald)