It was the latest clash in a tense standoff between the South American country’s socialist government and the centre right-dominated opposition.
“We are staying in the dialogue system but we are not going to take part in the meeting,” said Jesus Torrealba, leader of the opposition MUD coalition.
His side insists the government release jailed opposition leaders and agree to hold a vote on whether Socialist President Nicolas Maduro should stay in office.
Maduro has refused both demands, despite insisting he is open to dialogue.
The centre-right opposition blames Maduro’s management for a deep economic crisis.
Maduro says the crisis is a US-backed capitalist conspiracy. His number two Diosdado Cabello had insisted on Monday: “We will not withdraw from the talks.”
A recession driven by plunging prices for Venezuela’s crucial crude oil exports has led to shortages of food and medicine. Citizens face long queues to buy basic supplies and inflation has soared.
Deadly riots and looting have broken out over recent months. The dialogue aims to calm tensions as the centre-right opposition demands a vote on removing Maduro.
The MUD claimed Maduro’s side had agreed at the last round of talks to meet some of its demands. “The government is not only failing to fulfil its promises, it is denying all the agreements,” Torrealba said on the radio.
Maduro insists the issue of prisoners and a vote were never on the table.
A group of 14 jailed opposition leaders launched a hunger strike on Monday to demand the government release political prisoners and allow a vote to settle the crisis.
Analysts have warned there is a risk of unrest in Venezuela. Anti-government protests in 2014 led to clashes that left 43 people dead.
Maduro has the public backing of the military high command and of most state institutions.
Torrealba said his side would only meet with Vatican and regional Latin American mediators.
MUD sources said they did not rule out that the government might make “proposals” via the mediators to unblock the talks.
