Allies and adversaries of President Hugo Chavez have come to blows in Venezuela's National Assembly.

Several rival assembly members, including opposition politician Alfonso Marquina, approached the podium during a debate where senior government officials were taking questions from opposition politicians.

Mr Marquina complained that boisterous Chavez supporters inside the chamber should be silenced and angry congressmen in front of the podium began pushing and shoving, with Mr Marquina and pro-Chavez opponent Henry Villanueva exchanging blows.

Fellow assembly members, aided by security guards, separated the pair and the melee broke up after appeals for calm from the podium.

Afterwards, Foreign Minister Nicolas Maduro blamed opposition politicians for the violence.

Mr Chavez's opponents gained ground in September elections, winning 67 of the assembly's 165 seats and preventing the president and his allies from getting the two-thirds majority needed to pass some legislation.

The result has been a build-up in tension, with heated debates and parties trading insults and threats.