Lawyers for Julian Assange are taking action aimed at making President Donald Trump’s administration reveal charges “secretly filed” against the WikiLeaks founder.

They are also pressing Ecuador to protect him from being extradited to the United States if he leaves its embassy in London, where he has been living for over six years.

A 1,172 page application has been made to the Washington-based Inter-American Commission of Human Rights (IACHR), asking it to make an “urgent intervention” in the case.

Mr Assange was granted political asylum by the Ecuador government and has remained in the embassy since the summer of 2012, believing he will be extradited to the US if he leaves the building.

Restrictions were placed on his communications and visitors last year, described by WikiLeaks as an “isolation regime”.

The move on Wednesday follows a mistake in a document filed by the US authorities in an unrelated case last year which suggested criminal charges may have been prepared against Mr Assange in secret.

WikiLeaks said calls to extradite him to the US was the reason he obtained political asylum in 2012.

The Trump administration was accused of refusing to reveal details of charges against Mr Assange despite the fact that sources in the Department of Justice have confirmed that he has been charged under seal, his lawyers said.

“The revelation that the US has initiated a prosecution against Mr Assange has shocked the international community”, the legal submission stated.

The US government “is required to provide information as to the criminal charges that are imputed to Mr Assange in full”, it added.

The submission said that for the first time, US federal prosecutors have formally approached people in the United States, Germany and Iceland in recent months and pressed them to testify against Mr Assange in return for immunity from prosecution.

Baltasar Garzon, the international co-ordinator of Mr Assange’s legal team, said he was asking the IACHR to make an urgent intervention in his favour and was calling for “international solidarity for this case in which the right to access and impart information freely is in jeopardy”.

The application by Mr Assange’s lawyers identifies a raft of legal obligations that the US and Ecuador are “flouting” in their treatment of him.

The lawyers claim the Trump administration has been attempting to “pressure” Ecuador to hand over Mr Assange, including “serious overt threats” against Ecuador made by senior US political figures.

“Ecuador is required to end the regime of isolation imposed on Mr Assange, suspending the application of the so-called special protocol and guaranteeing his rights as an asylee will be respected in full,” the document filed by his lawyers stated.