By Renee Maltezou and Andreas Rinke BRUSSELS (Reuters) - Euro zone leaders argued late into the night with near-bankrupt Greece at an emergency summit, demanding that Athens enact key reforms this week to restore trust before they will open talks on a financial rescue to keep it in the European currency area. Leftist Prime Minister Alexis Tsipras was told to push legislation through parliament to convince his 18 partners in the euro zone to release immediate funds to avert a state bankruptcy and start negotiations on a third bailout programme estimated at up to 86 billion euros (62 billion pounds). Six sweeping measures including tax and pension reforms must be enacted by Wednesday night and the entire package endorsed by parliament before talks can start, a draft decision by Eurogroup finance ministers sent to the leaders showed.