Tens of thousands of Venezuelans mourned the passing of president Hugo Chavez on the first anniversary of his death on Wednesday.

But, while the ceremonies were taking place, National Guard troops had to fire teargas and rubber bullets at anti-government activists in cities across the country who insisted on continuing with violent street protests despite the commemorations.

During the ceremonies, President Nicolas Maduro angrily announced that he was ending diplomatic relations with Panama, which he accused of being a "lackey" of the US.

Mr Maduro said that Panama had attempted to refer the situation in Venezuela to the US-dominated Organisation of American States (OAS).

"We don't accept the interventionism of anyone, because our international policy is a policy of peace, of co-operation, of respect and of the anti-imperialist Latin American union," Mr Maduro said.

Panama's Foreign Ministry issued a statement expressing "astonishment" at the "unacceptable insults" and claiming unconvincingly that the request for the OAS to discuss Venezuela had not been intended as interference in the country's affairs.

Meanwhile, the right-wing protests continued as the middle classes insisted on ignoring the solemnity of the day.

In San Antonio de los Altos, in Miranda state, protesters blocked roads but were driven off by hundreds of National Guard troops, national police and other authorities with tear gas and rubber bullets.

Protests were also reported in Valencia, San Cristobal, Merida and Barinas.

Despite the protests, the anniversary of Chavez's passing was a time for sadness and reflection for most Venezuelans.

Thousands gathered in Caracas at the capital's parade grounds to honour the socialist leader who died of cancer on March 5 2013.

The military parade was attended by Chavez's international comrades Bolivian President Evo Morales, Nicaraguan President Daniel Ortega and Cuban President Raul Castro, among others, who addressed the massed Chavistas with recollections of their friend and comrade.

Afterward, they participated in a ceremony at Chavez's hilltop mausoleum, which was followed by the television premiere of Oliver Stone's documentary My Friend Hugo.