"Present and future projections leave no room for complacency," Tsipras said in a speech to parliament.

"To pay pensions in 2016, the social security system - apart from contributions and state funding - will need to find additional funds of 980 million euros," he said.

"We are choosing a difficult path, rather than this dead end."

(Reporting By Renee Maltezou, writing by Michele Kambas)