The families of four men who are set to be extradited from the UK to the US have protested outside Downing Street, claiming the men's right to a fair trial in their own country is being denied, and that the UK is treating them as enemies of the state.

The argument put forward by the families is an highlighted by the case of Wikileaks founder Julian Assange, who is wanted in Sweden on sex charges he denies.

His supporters say extradition to Sweden would be just the first step in Assange being handed over to the US because he has embarrassed the US government by leaking sensitive information.

The protesters presented a petition at 10 Downing Street. The British government is already in talks with the US with a view toward altering the extradition treaty.

Al Jazeera's Harry Smith reports from London.