Several other aircraft carrying Cristina Fernandez, Rafael Correa and Fernando Lugo, the presidents of Argentina, Ecuador and Paraguay respectively, as well as Jose Miguel Insulza, the head of the Organisation of American States (OAS), left Washington at the same time
They were expected to see what happened to Zelaya before deciding whether to land in Honduras.
Call for dialogue
Shortly after Zelaya left Washington, the aviation agency in Honduras said the jet had been directed to head for El Salvador.
It was not clear if the pilot would comply with the order.
If Zelaya does manage to set foot in Honduras, the interim government has said it will arrest him for 18 alleged criminal acts including treason and failing to implement more than 80 laws approved by congress since taking office in 2006.
As tensions rose, leaders of the interim government gave a televised news conference and called for dialogue with the OAS.
"The Republic of Honduras has communicated to the representative of the OAS in Tegucigalpa that it is willing, with the aim of conducting conversations in good faith with a mission of representatives of the secretary general," Martha Lorena Alvarado, interim deputy foreign minister, said.
The OAS, a hemispheric bloc dedicated to strengthening political co-operation and reforms, suspended Honduras's membership of the body on Saturday.
Lucia Newman, Al Jazeera's Latin America editor, said it was not clear if the OAS would agree to talk to what it calls an "illegitimate" government.
"They [the interim government] are trying to find a way out of this that will not result in Zelaya returning to power," she said from Tegucigalpa.
"They are trying to appease the international community, they are trying to sound conciliatory."
Roberto Micheletti, who was been sworn in as president after the coup, also told the news conference that the Nicaraguan military was moving towards their shared border.
"We have been informed that in the sector of Nicaragua some troops are moving toward the border," he said.
"I would like, respectfully to ask our Nicaraguan brothers not to cross our borders as we are gong to defend them."
A Nicaraguan army spokesman said that the Honduran accusations were "totally false".
Francisco Dominguez, the head of the centre of Brazilian and Latin American studies at Middlesex University in the UK, said he did not believe that there was any basis to the claims that the Nicaraguan military could become involved.
"I think it is a very desperate manoeuvre to divert attention from the crisis they are in the middle of," he told Al Jazeera. "I have never seen a regime so isolated as this one."
Riot police armed with batons and backed by water cannon tried to disperse supporters of Zelaya who had gathered outside the airport.
"We have no pistols or arms, just our principles," Rafael Alegria, one of the protest organisers, said.
|Riot police and troops have been deployed around the airport in Tegucigalpa [AFP]
"We have the legitimate right to fight for the defence of democracy and to restore President Zelaya."
Oscar Andres Rodriguez, the highest ranking Catholic Church official in Honduras, had earlier urged Zelaya not to come back.
"We think that a return to the country at this time could unleash a bloodbath in the country," Rodgriguez said on national television.
"To this day, no Honduran has died. Please meditate because afterwards it would be too late."
Colin Harding, a Latin America analyst in London, said Zelaya was "hoping to force a showdown" by returning to Honduras.
"I think he wants to provoke the interim regime in Honduras into trying to arrest him. I think there is a certain sort of martyrdom attitude in the air," he told Al Jazeera.
"It's possible that we've got brinkmanship here, which will lead to some sort of compromise, which may conceivably allow Zelaya to return at a later date, to bring forward the election date to save the face of both sides."
The president was removed from power as he was about to press ahead with a non-binding referendum that his domestic critics said was aimed at changing the constitution to enable him to run again for office.