TEGUCIGALPA – Honduras' political rivals were on a collision course on Monday after negotiations collapsed and deposed President Manuel Zelaya vowed to return home despite warnings from a defiant de facto government.

Zelaya says resistance is being organized in Honduras to pave the way for his return this weekend and that nobody can stop him. The interim government installed after his June 28 military ouster has threatened to crack down on any protesters who stir trouble.

The looming confrontation raises the specter of a repeat of clashes in which at least one protester was killed during Zelaya's abortive attempt to fly back into the Central American country on July 5. Troops blocked the runway and stopped him from landing.

I have no doubt that this will raise the tension levels, said Efrain Diaz, a political analyst with the Center for Human Development, a Honduran non-governmental organization. We could see violence if Zelaya tries to return by force.

Pro-Zelaya protesters plan a march to Congress in the capital Tegucigalpa on Monday, and have called for a two-day national strike on Thursday and Friday.

A police spokesman on Sunday appealed to children and the elderly to stay away from protests planned for this week, saying the security forces would not be tolerant with anyone who acts like a terrorist in our country.

Talks to end the crisis broke down Sunday when the interim government's delegation told the mediator, Costa Rican President Oscar Arias, that his proposal to reinstate the left-leaning Zelaya was unacceptable and meddling in Honduran affairs.

A somber-faced Arias, a Nobel Peace Prize winner, fretted that the collapse could lead to bloodshed and he called on the two sides to give him another 72 hours to try and solve the worst crisis in Central America since the Cold War.

What is the alternative to dialogue? ... What happens if, tomorrow, a Honduran shoots at a soldier and then a soldier shoots his gun at an armed citizen?, Arias said.

UNUSUAL COUP

Roundly shunned by the international community, interim President Roberto Micheletti, appointed by the Honduran Congress after the coup, has insisted from the outset that he will not allow Zelaya to finish his term.

He says Zelaya, who was expelled from the impoverished textile and coffee exporting country in his pajamas in the middle of the night, violated the constitution by seeking to lift presidential term limits.

The crisis is seen as a diplomatic challenge for U.S. President Barack Obama as he seeks a fresh start with Latin America despite ideological differences with vocal U.S. foes like Venezuelan President Hugo Chavez

The U.S. State Department put a positive spin on the crisis talks, issuing a statement on Sunday extolling progress made.

The Honduran coup, however, is an unusual case.

Unlike those that battered the region in the 1970s and 1980s, Zelaya's ouster was approved by Honduras' Supreme Court and Congress as well as Catholic Church leaders in the nation. There is also no military strongman in the picture this time.

And many Hondurans think Zelaya's removal was justified despite widespread disagreement with how it was done.

But Zelaya vows to return this coming Saturday or Sunday.

Absolutely no one can stop me. I'm a Honduran, it is my right, Zelaya told Reuters in a telephone interview from neighboring Nicaragua after the talks in Costa Rica stalemated.

Analysts say the interim government is digging in its heels so that Zelaya's reinstatement becomes a moot point. His term was due to end in January, and elections were scheduled for November.

The interim government, which has been denied around $200 million in multilateral aid and $16.5 million in U.S. military aid and is at risk of regional trade sanctions, can take all necessary pressure, said Rene Zepeda, Micheletti's spokesman.

(Additional reporting by Juana Casas and Gustavo Palencia in Tegucigalpa, John McPhaul in San Jose, and Tim Gaynor in Washington; Writing by Simon Gardner; Editing by Paul Simao)

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