Nazi agents in Chile plotted to destroy the Panama Canal around the time of the Second World War, declassified files show, an act that would have changed the "history of the whole world".

One lawmaker suggested the documents, which were made public on Thursday by the Chilean equivalent of the FBI, could also indicate there were business or political figures in the South American country at the time who backed the Nazis.

According to the 1937-1944 files released by Chile's investigations police, the force's counterintelligence unit thwarted the plan after it detained the people leading it in the country's main port of Valparaiso. No other details on the plot were provided.

The head of Chile's investigations police said the Department 50 unit also dismantled two Nazi espionage networks operating in Chile at the time.