The United States has struck targets in Venezuela as the move signals a further escalation in the dispute.

Since September, the US military has already carried out several operations against boats allegedly transporting drugs in the Caribbean and the Pacific.

Venezuela has been governed by the left-wing authoritarian politician Nicolás Maduro since 2013. After his re-election last year, a vote clouded by allegations of fraud, he was sworn in for another term running until 2031. International organisations and human rights groups accuse his government of suppressing political opponents, carrying out arbitrary arrests, and permitting torture and violence. Despite sizeable protests in parts of the country, Mr Maduro remains firmly in power, largely because the armed forces continue to support him.

The opposition leader María Corina Machado was awarded this year’s Nobel Peace Prize for her campaign for a peaceful transition from dictatorship to democracy. She reached Oslo only hours after the official ceremony, having left Venezuela in secret.

Ms Machado had been in hiding for more than a year while under investigation on charges including treason. Prosecutors had warned that she would be classed as a fugitive if she left the country. Any return to Venezuela could expose her to severe measures, including arrest or a ban on entry.

Venezuela holds the world’s largest proven oil reserves, estimated at 303 billion barrels. Much of this is heavy crude, which requires specialised technology for extraction and refining. Despite these vast resources, current output stands at about one million barrels a day. Two decades ago, production was close to three million barrels daily. Sanctions, mismanagement at the state oil company PDVSA, and corruption have all played a part. This year, the US company Chevron resumed production in the country.

In mid-December, US troops boarded a Venezuelan oil tanker, an incident that marked a further rise in tensions. Washington said the vessel formed part of an illegal oil network intended to support foreign terrorist groups. Caracas described the action as an act of international piracy by the United States.

In spite of its oil, gold and rare earth minerals, Venezuela faces deep poverty. According to the Venezuelan Observatory of Finance, 86 per cent of households live below the poverty line. Average monthly household income stands at 231 US dollars, while the cost of a basic food basket for a family is 391 dollars. Many families rely on money sent home by relatives living abroad.

Economic collapse, state repression and violence have driven a mass exodus from Venezuela. Large numbers of skilled workers have also left. The United Nations estimates that 7.9 million Venezuelans have emigrated, roughly a quarter of the population. Most live in neighbouring Latin American states, while others head for the United States or Europe. This year, Venezuelans formed the largest group of asylum seekers in the European Union.

Maduro presents himself as a defiant opponent of the United States in its own region. He frequently denounces what he calls US imperialism and portrays Venezuela as a model socialist state. His government receives backing from the left-wing administrations in Cuba and Nicaragua. Cuban intelligence officers are said to assist in maintaining discipline within the Venezuelan armed forces. Russia, China and Iran also count among Caracas’s allies.