Bradley Manning, the US soldier held for allegedly leaking secret government files, is a “gay hero”, rights campaigner Peter Tatchell has claimed.

Mr Tatchell said that if Mr Manning had leaked the documents to WikiLeaks, he should be praised as a human rights defender.

The former military intelligence analyst has been held in custody for the last year. He was arrested in May 2010 in Iraq on suspicion of passing restricted material to the whistleblower website and has been charged with 34 offences, including making information available to the enemy.

While the charges he faces carry a maximum penalty of death, US military prosecutors have said they will not seek this. Instead, he may face life in prison if convicted.

The material in question included 700,000 US diplomatic and military cables and footage of a July 2007 airstrike on Baghdad. The 23-year-old’s supporters claim that the leaked files expose civilian deaths which had been covered up by the military.

Mr Manning is gay but was unable to declare his sexual orientation under the US military’s Don’t Ask, Don’t Tell policy.

Speaking today, Mr Tatchell said that the soldier was “inspired by his commitment to human rights” and had attended gay Pride marches and campaigned against bans on out gay troops and same-sex marriage.

Describing Mr Manning as a “humanist and a man with a conscience”, Mr Tatchell said he had allegedly been driven to release the files because he “became disillusioned with his country’s foreign and military policy [and believed] it was betraying the US ideals of democracy and human rights”.

“It is only (allegedly) thanks to Bradley Manning that we now know the truth about this slaughter of innocent civilians – and about the killings of hundreds of other civilians in unreported and undocumented incidents,” Mr Tatchell said.

The soldier, who is waiting to hear if he will face a court martial, was recently moved to another jail after concerns were raised about his well-being.

He was required to strip regularly and was held in a bare cell. Last month, he was moved to a medium-security prison in Kansas following lengthy assessments. He is now able to live alongside other prisoners and his surroundings have been described as more comfortable.

Mr Manning’s mother Susan, who is Welsh, criticised British MPs last month for not helping him.

The Foreign Office said last month that the British embassy in Washington had relayed MPs’ concerns about Mr Manning’s treatment to the White House.

Mr Tatchell has urged Mr Manning’s supporters to take action, including writing to the soldier, contacting their MPs and lobbying the US embassy in London.