Venezuelan opposition lawmakers relaunched efforts to drive President Nicolas Maduro from power on Tuesday after negotiations to ease the countrys political and economic crisis stalled.

Deputies in the National Assembly made a declaration ruling that the socialist president bore "political responsibility" for the crisis and urged state attorneys to investigate him with a view to prosecution.

Maduro has consistently blocked efforts by the legislature to challenge his power since the opposition took over the assembly in January.

He retains the support of the military and key state institutions including the Supreme Court, which has frequently overruled the legislative assembly.

Maduro's allies in the assembly boycotted Tuesday's session, branding the motion a "coup d'etat."

Tuesday's move "is a blow from the legislature, but it does not mean the president will be deposed," legal expert Pedro Afonso Del Pino told AFP earlier, anticipating the lawmakers' declaration.

An economic crisis fueled by falling prices for Venezuela's crucial oil exports has led to food shortages and riots over recent months.

The socialist president says the crisis is a US-backed conspiracy. The opposition blames his economic management.

"This is going to heat up the political process in Venezuela," said political scientist Carlos Romero of Tuesday's move.

"It is going to make the situation worse."