WASHINGTON (Reuters) - US President Donald Trump has intervened in high-profile cases of three military personnel convicted of war crimes in Iraq and Afghanistan.

"For more than 200 years, presidents have used their authority to offer second opportunities to deserved military personnel who have served our country," the White House said in a statement. "These measures are consistent with this long history."

A Pentagon spokesman said the department has confidence in the military justice system, adding that "the president is part of the military justice system as the supreme commander and has the authority to assess things that way."

Trump has previously expressed support for the three military personnel - Clint Lawrence, Matthew Golstein and Edward Gallagher - and their issues are separate, two in Afghanistan and one in Iraq.

In 2013, prosecutors accused Lawrence of unlawfully ordering the shooting of two men on motorcycles while on patrol in Kandahar province, Afghanistan, and convicted Lawrence of two murders.

Last year, Golesteen, an Army Special Forces officer, was charged with killing an Afghan in Afghanistan in 2010.

Golstein was awaiting trial for murder, while Lawrence was serving a 19-year sentence, but Trump granted them a full pardon.

Gallagher, a platoon commander of the US Navy Special Forces and a medalist, was also charged with various war crimes while in Iraq in 2017.

In July, a military jury acquitted Gallagher of murdering an ISIS detainee by stabbing the injured detainee in the neck, but was convicted of illegally photographing himself with the body of the detainee, which led to his demotion, but Trump reinstated him.

The New York Times reported earlier that some senior officials, including Defense Secretary Mark Esper, oppose amnesty for the soldiers, noting that the move would undermine justice and serve as a bad example.