The Honduran interim government defied international pressure on Wednesday and vowed there was "no chance at all" of ousted President Manuel Zelaya returning to office.

World leaders from U.S. President Barack Obama to Venezuelan President Hugo Chavez have told the new rulers of the Central American country to restore Zelaya, a leftist who was toppled by the army on Sunday and sent into exile after a dispute over presidential term limits.

The Organization of American States gave Honduras an ultimatum early on Wednesday to allow Zelaya back into office by this weekend or face suspension from the hemispheric group.

But the response from the interim government indicated there was little immediate hope of a negotiated solution to the crisis in Honduras, an impoverished coffee and textile producer.

Enrique Ortez, interim foreign minister, told Reuters that Zelaya would be arrested if he came home.

"We are not negotiating national sovereignty or the presidency," he said in an interview. "There is no chance at all," of Zelaya coming back to power.

The crisis in Honduras has spiraled into the worst political turmoil in Central America since the U.S. invasion of Panama in 1989, posing a test both for regional diplomacy and for Obama's ability to improve the United States' battered standing in Latin America.

Ortez said that interim government had dropped a plan to send a delegation to Washington for talks, but a mission from four countries of the OAS would visit Honduras this week.

However, in Washington, an OAS spokesman said that he was unaware of any plans to send a mission this week.

Zelaya, who took office in 2006 and had been due to leave power in 2010, was forced out over his push to extend presidential mandates beyond a single four-year term.

Since coming to power in 2006, Zelaya has become a divisive figure in Honduras, an coffee, textile and banana-exporter of 7 million people, especially after he allied himself with firebrand socialist Chavez.

Public support for the wealthy businessman had dropped as low as 30 percent in recent months, with many Hondurans uncomfortable over his tilt to the left in a country with a longtime conservative, pro-Washington position.

The crisis has produced a challenge for Obama as he seeks to improve ties with Latin America.

The Pentagon said on Wednesday the U.S. military had postponed activities with its Honduran counterpart while the Obama administration reviewed the situation in Honduras.

The U.S. military has a task force of about 600 troops stationed at a Honduran base northwest of the capital city. Honduras was a U.S. ally in the 1980s when Washington helped Central American governments fight Marxist rebels.

The crisis in Honduras erupted as the country struggles with a sharp decline in remittances from Hondurans living in the United States and in vital textile exports. Thousands of jobs have already been lost due to the slowdown in exports.

But coffee producers told Reuters exports had not been affected even after protesters blocked major highways in the interior of the country.

Several thousand demonstrators on Tuesday rallied to applaud Zelaya's ouster in the capital Tegucigalpa, after a day of clashes between riot police and the toppled leader's supporters broke out near the presidential palace.