Haiti's ruling party announced Wednesday that President Rene Preval's chosen successor is withdrawing from the disputed race for president under pressure from the U.S., the Organization of American States and local protests.

But it was not immediately clear if the Unity party's statement was enough to end the candidacy of government construction official Jude Celestin, who had been heading to a runoff vote against former first lady Mirlande Manigat. Rival candidates and some foreign governments have questioned the results of the first round of voting that put in Celestin in second place.

Electoral council spokesman Pierre Thibault Junior told The Associated Press that the council "has not received anything formally" from the Celestin campaign.

Haitian leaders have come under strong pressure from Washington, the OAS and others to drop Celestin from the two-person runoff in favor of Manigat and popular singer Michel "Sweet Micky" Martelly.

The December release of preliminary results showing Celestin edging out Martelly for the last spot in the runoff triggered widespread protests and rioting in major Haitian cities.

Disgust with the once-popular Preval soared both in the streets of Haiti and in some international circles following the January 2010 earthquake over what was seen as ineffective leadership as millions suffered in homeless camps and broken buildings. Celestin was seen as his "dauphin," or royal heir.

An OAS-sponsored team of experts was called in to sort out the electoral mess. That analysis, which is not universally accepted, said their analysis showed that tossing out fraudulent ballots resulted in Martelly finishing second. It was seized on by the United States, France, Canada and others, many of whose officials had questioned the announced first-round results as soon as they were released.

Wednesday's statement from the Unity party officials, whose faction is known as Inite in Creole, said their decision was aimed at maintaining stability in the politically fragile country under what it deemed the threat of an embargo from the international community.

"Unity understand the game very well," said the letter written in Haitian Creole and distributed to journalists. "Because Unity does not want the people to suffer even more, we chose not to provoke the international community over the election."

"We thank Jude for understanding the situation, though neither he nor we agree with the way things have occurred."

The Unity party coordinator, former Sen. Joseph Lambert, confirmed the letter from himself and other senior party officials including Kelly Bastien, Levaillant Louis Young and Joseph Moliere.

But he told AP by text message that: "It's only Celestin who can (drop) out of the race legally."

Celestin, who has made few statements to the media during his campaign, has not commented so far.

The Martelly campaign said it was reviewing the situation.

The U.S. Embassy in Port-au-Prince said it was not sure that the embattled president's successor was really out of the race.

"We're still monitoring the situation which is very fluid and we're continuing to seek an electoral outcome that reflects the will of the Haitian people," spokesman Jon Piechowski told AP.

The U.S., which currently holds nearly $1 billion in reconstruction aid originally promised for last year, is insisting on the OAS recommendations in order to guarantee "sustained support from the international community, including the United States." The U.S. State Department also confirmed it had revoked the visas of about a dozen Haitian officials amid the controversy.

"It's not that we are picking one (candidate) over the other. It's that there are strong indications that there was significant voter fraud, that the preliminary findings do not reflect the actual voting of the Haitian people," State Department spokesman P.J. Crowley told reporters Wednesday before the announcement.

Among the vocal critics of the OAS recommendations has been a left-leaning Washington think tank, the Center for Economic and Policy Research, which maintains that the entire election should be thrown out.

One of its principal objections is the exclusion of the Fanmi Lavalas party of ousted former President Jean-Bertrand Aristide.

"The U.S., France, Canada and other actors in the international community have no justification to demand that the Haitian government adopt the OAS Mission's conclusions," CEPR's Dan Beeton said in an email to journalists.