Panorama found evidence the state had covered up killings of civilians by UK troops in Iraq and Afghanistan.

The ICC said it took the findings very seriously. The MoD has said the allegations are unsubstantiated.

The MoD said it had co-operated fully with the ICC and saw no justification for further interventions by the court.

Prime Minister Boris Johnson's spokesman said the allegations against the MoD are "untrue".

Public inquiry

A formal investigation by the ICC, based in The Hague in the Netherlands, would be the first time it has taken action against any UK nationals for war crimes.

The ICC's Office of Prosecutor said it would "independently assess" the findings of Panorama, which could be "highly relevant" to their decision whether to open a landmark investigation into the UK.

The court has previously concluded there is credible evidence that British troops committed war crimes in Iraq.

Most of those cases involve allegations of the mistreatment of detainees.

The best known is that of Baha Mousa, a hotel worker in Basra who died after being tortured and beaten by British troops in 2003. It led to a public inquiry and the only conviction of a British soldier for war crimes in Iraq.

However, Panorama, working with the Sunday Times, has uncovered new information about alleged killings in British custody.

Detectives from the Iraq Historic Allegations Team (IHAT), which investigated alleged war crimes committed by British troops during the occupation of Iraq, say they found evidence of widespread abuse occurring at a British army base in Basra three months before Mousa was killed.

It happened at Camp Stephen, run by the Black Watch, 3rd Battalion, Royal Regiment of Scotland. IHAT investigated the deaths of two men, who died within a week of each other, in May 2003. The MoD accepts both were innocent civilians.

IHAT gathered statements from British soldiers and army staff that described how the two men were tortured before being found dead with bags tied over their heads.

This summer, British military prosecutors decided no-one would be prosecuted in connection with the two deaths.

When he was shown Panorama's evidence, former Director of Public Prosecutions Lord Macdonald said he thought it was "staggering" that no soldier had been charged.

"I think the conclusion begins to become rather obvious, that prior to their deaths, it's overwhelmingly likely that these men were physically abused."

'Extensive investigation'

On Sunday, Foreign Secretary Dominic Raab told the BBC "all of the allegations, that had evidence, have been looked at".

A No 10 spokesman said that the service police had already carried out "an extensive investigation" about the conduct of forces in Iraq and Afghanistan - and the independent Service Prosecuting Authority had decided not to prosecute any of the cases.

The MoD said military operations are conducted in accordance with the law and there had been an extensive investigation of allegations.

"Investigations and decisions to prosecute are rightly independent from the MoD and have involved external oversight and legal advice," a spokesperson told the BBC.

"After careful consideration of referred cases, the independent Service Prosecuting Authority decided not to prosecute."

"The BBC's claims have been passed to the Service Police and the Service Prosecuting Authority who remain open to considering allegations."