Tensions have run high in Venezuela amid uncertainty over the future of Chavez, who missed his own inauguration on January 10 and has not been seen in public since he traveled to Cuba last month for his latest cancer surgery.

A coalition of several opposition parties said a rally would be held in a public park to commemorate the 55th anniversary of the country's democracy on Wednesday, instead of a previously planned march through the capital.

Chavez's United Socialist Party had called for its own demonstration on Wednesday, which marks the anniversary of the end of the rightwing military dictatorship of General Marcos Perez Jimenez in 1958.

The opposition coalition said its decision to call off the march "reaffirms its commitment to peace," adding that "the national government has clear intentions to take to the streets of the capital with the purpose of inciting violence."

The opposition has called for the appointment of an interim president to rule until new elections can be held, while the ruling party insists the ailing Chavez -- re-elected to a third six-year term in October -- is able to fulfill his duties from his hospital bed in Cuba.

The 58-year-old firebrand has been the face of the Latin American left for more than a decade and has dominated the political scene in Venezuela, which has the world's largest proven oil reserves.

The normally highly visible president has not been seen for weeks, however, and while officials say he is recovering they have never disclosed the type or severity of his cancer, first made public in 2011.