Qatar says the ceasefire between Israel and Hamas will go into effect at 8:30 a.m. local time (0630 GMT) on Sunday.

Israel and Hamas are once again struggling to reach a ceasefire that could wind down the 15-month war in Gaza and bring home dozens of Israelis held hostage.

Hamas’ demand that Israel release Marwan Barghouti brings new attention to a man many Palestinians see as their Nelson Mandela.

Hamas officials say the group is studying a proposed cease-fire deal that would include prolonged pauses in fighting in Gaza and swaps of Israeli hostages for Palestinian prisoners, but the militants appeared to rule out some key components.

Marwan Barghouti, a popular Palestinian uprising leader imprisoned by Israel has submitted an independent list of candidates to run in the upcoming parliamentary elections. Polls indicate it would split the vote for Fatah, potentially paving the way for another major victory by Hamas. That increases the likelihood that Abbas will find a way to call off the first Palestinian elections in 15 years. But he remains a popular and charismatic leader, and by breaking with Abbas he could reshape Palestinian politics and potentially replace him as president. Polls consistently show him to be the most popular Palestinian leader, with support from across the political spectrum.