Leftist Latin American leaders rallied around ousted Honduran President Manuel Zelaya and tried to thrash out a response to an army coup that sparked protests in the impoverished nation and drew worldwide condemnation.

Pro-Zelaya demonstrators defied an overnight curfew and held a vigil by the presidential palace in Tegucigalpa, while Venezuela's firebrand President Hugo Chávez led talks with Zelaya and other allies in neighbouring Nicaragua.

The coup is the biggest political crisis to hit Central America in years and will test US President Barack Obama as he tries to mend Washington's battered image in Latin America.

The Organization of American States (OAS) demanded Zelaya's immediate return, saying no other government would be recognized.

The US goal following a weekend coup in Honduras is to restore democratic order in the Central American country, the White House said.

White House spokesman Robert Gibbs said he did not believe President Barack Obama had spoken to Honduran President Manuel Zelaya since the ouster. The United States had worked to avert the type of "constitutional action" that took place, Gibbs said.

US President Barack Obama said his government believed the weekend coup in Honduras was "not legal" and that ousted President Manuel Zelaya remained the country's leader.

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