WikiLeaks founder Julian Assange and socialite Jemima Khan led a protest in London Saturday against the war in Afghanistan, 10 years after the United States and Britain went to war against the Taliban.

Organisers the Stop The War Coalition claimed 5,000 people attended the protest in central London's historic Trafalgar Square. London's Metropolitan Police did not give a figure.

"There comes a moment when you have to ask what is more dangerous, terrorism or counterterrorism," Khan, the former wife of Pakistani cricketer turned politician Imran Khan, told the crowd.

"Afghanistan is still the worst place in the world for women to live.... So by any standards, our mission in Afghanistan has failed."

Assange, who is currently under strict bail conditions as he fights extradition from Britain to Sweden on charges of rape, compared journalists and soldiers to war criminals.

"When we understand that wars come about as a result of lies, peddled to the British public and the American public and public all over Europe and other countries, then who are the war criminals? It is not just leaders, it is not just soldiers, it is journalists, journalists are war criminals," said Assange.

Assange, whose anti-secrecy website has published tens of thousands of leaked US diplomatic cables, won the Martha Gelhorn Prize for journalism in June.

Britain is the second biggest contributor of troops in Afghanistan after the United States, with 9,500 troops in the country.

A total of 382 British troops have died there since the beginning of military operations in Afghanistan in October 2001, which were launched following the 9/11 attacks on New York and Washington.

Western combat troops are due to pull out of Afghanistan by the end of 2014 but a survey published Thursday showed 57 percent of Britons want them to be withdrawn immediately.