The governing party candidate in Haiti’s disputed presidential election, Jude Celestin, is to withdraw from the second round, his supporters say.
The decision follows international pressure on Mr Celestin to quit after monitors found that first round results had been rigged in his favour.
It clears the way for a delayed run-off between former first lady Mirlande Manigat and pop star Michel Martelly.
The US and UN have both called on Mr Celestin to pull out of the race.
Senators from the governing Inite coalition said Mr Celestin was about to write to the Provisional Electoral Council.
“Jude Celestin will withdraw from the presidential race to facilitate a solution to the electoral crisis,” Senator Franky Exius told Reuters news agency.
Observers said the first round of the election in November was marred by widespread fraud.
Preliminary results put Mr Celestin in second place behind Mrs Manigat, with Mr Martelly in third.
But this provoked violent protests by Mr Martelly’s supporters, who said the result had been fixed by the government to ensure Mr Celestin – who was backed by outgoing President Rene Preval – went through to the second round.
The run-off was delayed while experts from the Organisation of American States analysed the results.
They found in Mr Martelly’s favour, and recommended Mr Celestin be dropped from the race because of irregularities in the tally.
President Preval and the electoral council have been under growing international pressure to accept that recommendation.
The US has led warnings that Haiti must install a credible government or risk losing international aid and support.
Last week UN peacekeeping chief Alain Le Roy warned that Haiti could face a constitutional crisis with the possibility of “considerable unrest and insecurity” if Mr Celestin did not withdraw.
Political tension has been further heightened by the return to Haiti of the former leader, Jean-Claude “Baby Doc” Duvalier, after 25 years in exile.
The second round was supposed to take place on 16 January but was postponed because of the dispute.
Whoever eventually wins the election will the task of rebuilding Haiti after the devastating earthquake of just over a year ago, which killed around 250,000 people and left the capital, Port-au-Prince, in ruins.