THE British government interfered in two elections in Chile to prevent socialist leader Salvador Allende winning power, declassified Foreign Office papers have revealed.

The documents unveil for the first time Britain’s covert role in preparing the ground for General Augusto Pinochet’s bloody military coup in 1973, according to a report published today by investigative website Declassified UK. 

They show that Harold Wilson’s Labour government helped the US to meddle in the 1964 and 1970 elections in an effort to prevent Mr Allende, Chile’s leading socialist, from coming to power.

A secret unit within the Foreign Office called the information research department (IRD) launched  a propaganda offensive to smear Mr Allende and lend legitimacy to his main opponent, Christian Democrat Eduardo Frei.

The socialist candidate lost to Mr Frei in 1963 but won the 1970 election.

The report states that the Labour government considered Mr Frei’s election success in 1963 a “landmark victory,” with a minister at the time describing it as a “victory against the communists to press home.”

As support for Mr Allende grew in the run-up to the 1970 election, the Foreign Office escalated its propaganda offensive, deploying a specialist field officer to Santiago who was tasked with thwarting a socialist victory.

A few weeks before voters went to the polls, an IRD officer told British ambassador David Hildyard that “the IRD operation … has been concentrating on preventing an extreme-left alliance from gaining power in the 1970 presidential elections.”

The Chilean military’s overthrow of Allende’s government – with US support – ushered in 17 years of brutal dictatorship under Gen Pinochet, during which 40,000 people were tortured, 3,200 killed or “disappeared” and more than 200,000 forced into exile.