Zimbabwe's former vice-president, whose sacking led to the shock resignation of long-time leader Robert Mugabe, could be sworn in as the new president within hours, the ruling party says, according to BBC.Emmerson Mnangagwa, who fled to South Africa two weeks ago, is due to arrive back on Wednesday, the Zanu-PF says. His dismissal led both the party and the military to intervene and force an end to Mr Mugabe's 37-year long rule. The news sparked wild celebrations across the country late into the night. The announcement that the 93-year-old was stepping down came in the form of a letter read out in parliament on Wednesday, abruptly halting impeachment proceedings against him. In it, Mr Mugabe said he was resigning to allow a smooth and peaceful transfer of power, and that his decision was voluntary. A Zanu-PF spokesman said Mr Mnangagwa, 71, would serve the remainder of Mr Mugabe's term until elections which are due to take place by September 2018. He is expected to land back in Zimbabwe at 11:30 GMT and later be sworn-in, an ally to the former vice-president, Larry Mavhima, told Reuters news agency. "Together, we will ensure a peaceful transition to the consolidation of our democracy, and bring in a fresh start for all Zimbabweans and foster peace and unity," Mr Mnangagwa said in comments to Zimbabwe's NewsDay on Tuesday. Mr Mnangagwa's firing by Robert Mugabe two weeks ago triggered an unprecedented political crisis in the country. It had been seen by many as an attempt to clear the way for Grace Mugabe to succeed her husband as leader and riled the military leadership, who stepped in and put Mr Mugabe under house arrest. The move to appoint Mr Mnangagwa as Robert Mugabe's successor appears to go against the constitution, which would normally give the post to the serving vice-president, Phelekezela Mphoko. Mr Mphoko - a key ally of Grace Mugabe - is not believed to be in the country. Some have questioned whether the handover to Mr Mnangagwa will bring about real change in the country. Opposition leader Morgan Tsvangirai told the BBC he hoped that Zimbabwe was on a "new trajectory" that would include free and fair elections. He said Mr Mugabe should be allowed to "go and rest for his last days".