London: Australian government officials have paid a mysterious visit to Julian Assange in his Ecuadorian embassy refuge in London, in a sign there may be a breakthrough in the stalemate that has lasted almost six years.

Two officials from Australia's High Commission were spotted leaving the embassy in Knightsbridge in west London on Thursday.

Julian Assange greets supporters outside the Ecuadorian embassy in London in 2017. Credit:AP

It is the first time Australian consular officials have visited Assange at the embassy.

They were accompanied by Assange's lawyer Jennifer Robinson.