Donald Trump announced Monday he will nominate retired general John Kelly to head the Department of Homeland Security, the third ex-military man tapped for a top job in his presidential administration.

'General John Kelly's decades of military service and deep commitment to fighting the threat of terrorism inside our borders makes him the ideal choice to serve as our Secretary of the Department of Homeland Security,' Trump said in a statement.

'He is the right person to spearhead the urgent mission of stopping illegal immigration and securing our borders, streamlining TSA (Transportation Security Administration) and improving coordination between our intelligence and law enforcement agencies,' Trump said.

Meeting: Retired General John Kelly met Trump at his Bedminster, New Jersey golf club late in November. His nomination to lead the Department of Homeland Security is now official

John Kelly is being nominated for Homeland Security. He met with the president-elect on November 30 and the transition team made his nomination official today

Kelly led the US Southern Command, covering US military operations in Central and South America and the Caribbean, including efforts to stem the flow of illegal drugs across the US southern border and end human trafficking.

'I am humbled and grateful to be nominated to serve in President-elect Trump's cabinet as Homeland Security Secretary,' Kelly said in the statement issued by the president-elect.

'The American people voted in this election to stop terrorism, take back sovereignty at our borders, and put a stop to political correctness that for too long has dictated our approach to national security.

'I will tackle those issues with a seriousness of purpose and a deep respect for our laws and Constitution. I am honored for the opportunity to be back in the service to our country, and our people.'

The third general chosen for Trump's cabinet, Kelly spent 45 years in the US Marines, holding a range of positions from field commands in Iraq to political liaison in Congress before finishing his career as commander of the US armed forces Southern Command.

A Boston native, Kelly joined the Marines in 1970 and retired from the force in January of this year.

He is also the highest ranking military official to have lost a child in combat.

1st Lieutenant Robert Michael Kelly, the nominee's 29-year-old son, was killed in Afghanistan on November 9, 2010.

The younger Kelly stepped on a landmine and was killed instantly.

Previous to that, he had been involved in some of the fiercest fighting against the Taliban, leading a platoon of Marines in Sangin, Afghanistan.

'He went quickly and thank God he did not suffer,' John Kelly said of his son's landmine death in Afghanistan in 2010

'He went quickly and thank God he did not suffer', John Kelly said of his son's death, according to the Los Angeles Times. 'In combat that is as good as it gets.'

Trump also chose retired Marine General James 'Mad Dog' Mattis to lead his defense department and retired Lt. Gen. Michael Flynn as national security advisor.

Presidential historian Doris Kearns Goodwin remarked yesterday on 'Meet the Press' that Trump's selection of generals for his cabinet was 'a great thing.'

'I mean they know leadership more than anybody else,' she explained.

'They're not going to send people into battle as easily as they need to,' she added.