Greek Prime Minister Alexis Tsipras will resign on Thursday to pave the way for early elections on Sept. 20, government officials said, hoping to quell a rebellion in his leftist Syriza party and seal support for a bailout programme. Tsipras’s decision to return to the ballot box after seven bruising months in power deepens political uncertainty on the very day Greece began receiving funds under its third bailout programme with foreign creditors. “The aim is to hold elections on Sept. 20,” a government source said after Tsipras held talks with his advisers.