Mexican leftist leader Andres Manuel Lopez Obrador to leave hospital after heart surgery

Mexican leftist leader Andres Manuel Lopez Obrador will be released from the hospital on Saturday after a heart attack sent him into surgery earlier this week, undermining his ability to lead protests against a controversial energy reform.

Lopez Obrador, who was runner-up to Enrique Pena Nieto in last year's presidential election, is perceived as one of the biggest threats to the planned reform to open the state-controlled oil sector to private investment.

The reform, originally presented by Pena Nieto in August, is expected to be unveiled later on Saturday. A top lawmaker told Reuters the draft bill includes contracts ranging from profit-sharing and risk-sharing to licenses.

Lopez Obrador, who was admitted to hospital on Tuesday, will be required to rest for four weeks, according to a press statement.