Donald Trump touched down at the Dover Air Force Base in Delaware where he respectfully saluted the caskets carrying the remains of the four Americans tragically killed in a suicide bomb attack in Syria.

The president visited the base to pay tribute to the lives lost in the deadly attack on Wednesday in the northern Syrian town of Manbij.

The president looked serious as he raised his arm during the moving ceremony that honored Army Chief Warrant Officer 2 Jonathan R. Farmer, Navy Chief Cryptologic Technician Shannon M. Kent, former Navy SEAL and civilian Scott A. Wirtz and Arabic translator Ghadir Taher.

At least 19 people including the four Americans were killed when a suicide bomb detonated in a restaurant in the town on Wednesday, marking the deadliest assault on U.S. troops in Syria since American forces moved into the war-torn country in 2014.

President Donald Trump saluted the military honor guard that carried the remains of Scott Wirtz, one of the four Americans killed in a bomb blast in Syria on Wednesday. He honored them at a transfer ceremony at the Dover Air Force Base in Dover, Delaware on Saturday

Prior to landing at the Dover Air Force base he told reporters: 'When I'm going to meet relatives of some of our great, great heroes that have fallen, I think it might be the toughest thing I have to do as president'

A U.S. Navy carry team moved the transfer cases of the American victims to the Dover Air Force base on Saturday, three days after the bomb blast in Syria

Trump and Secretary of Stat Mike Pompeo watched on as the Navy's carry team brought over the remains of Scott A. Wirtz who died in the violent suicide bomb attack in Manbij, Syria earlier this week

Victims Farmer, Kent, and Wirtz were identified by the Pentagon. The fourth victim was not named by the Pentagon but was said to be an interpreter.

She was later named as Ghadir Taher, a 27-year-old Arabic interpreter from Georgia.

Her brother confirmed her death in a statement issued by Valiant Integrated Services, the defense contractor that hired her, according to the Washington Post.

'We are extremely saddened by the tragic and senseless passing of Ghadir Taher. She was a talented and highly-respected colleague loved by many who will be dearly missed,' a Valiant spokesperson said.

The Islamic State group has claimed responsibility for Wednesday's attack.

Prior to heading to the base Trump said: 'I think it is the toughest thing I have to do. When I'm going to meet relatives of some of our great, great heroes that have fallen, I think it might be the toughest thing I have to do as president.'

The Americans killed in a suicide bomb blast in Syria on Wednesday have been identified as Army Chief Warrant Officer 2 Jonathan R Farmer, 37, of Boynton Beach, Florida (left) and Navy Chief Cryptologic Technician (Interpretive) Shannon M Kent, 35, (right) of upstate New York

Defense Department civilian Scott A Wirtz (left) of St Louis, Missouri, was also killed in the attack. The fourth victim is believed to be interpreter Ghadir Taher (right) of Georgia

President Donald Trump pictured boarding Air Force One Saturday morning to head to Dover Air Force Base in Delaware to pay tribute to the four Americans who were killed during a suicide bomb attack in Syria on Wednesday

Trump walks with Pompeo (center) and acting U.S. Secretary of Defense Patrick Shanahan (second left) to meet the families of the four Americans who died in Syria after the suicide bomb attack

They walked onto a C-17 aircraft as the remains of the four Americans were returned to Dover Air Force Base from Syria on Saturday

With his eyes closed he paid his respects as guards moved the body of former Navy Seal who was working for the Defense Intelligence Agency

The transfer case was loaded into a vehicle then given a final salute

A member of the Air Force is seen securing the remains of Scott A Wirtz into a van during a dignified transfer ceremony

President Donald Trump pictured walking with acting Secretary of Defense Patrick Shanahan back onto Air Force One to return to Washington DC

'I've always said who are we killing ISIS for? You know, the worst enemy of Russia, Iran, Syria, you look at it, is ISIS. So we're killing ISIS for people that aren't necessarily always in agreement with us, let's put it that way. We have gone into Syria and in two years we have I guess reduced it to 99% of the territorial caliphate,' he added.

'We've been hitting ISIS very hard over the last three weeks ... and it's moving along very well,' the president said on American forces on the ground in Syria.

The attack comes about a month after Trump announced that ISIS militants were defeated and he will withdraw U.S. forces from Syria.

The bomb highlighted just how strong ISIS' grip on Syria still is and could complicate Trump's withdrawal plan. Some of his senior advisers have disagreed with the decision and have offered an evolving timetable for the removal of the approximately 2,000 U.S. troops.

Over the past month, Trump and others have appeared to adjust the Syria pullout timeline, and U.S. officials have suggested it will likely take several months to safely withdraw American forces from Syria.

In a December 19 tweet announcing the withdrawal, Trump had said, 'We have defeated ISIS in Syria, my only reason for being there during the Trump Presidency.'

He said the troops would begin coming home 'now.'

That plan triggered immediate pushback from military leaders and led to the resignation of Defense Secretary Jim Mattis.

A leading U.S. voice on foreign policy, Sen. Lindsey Graham, said during a visit Saturday to Turkey that an American withdrawal from Syria that had not been thought through would lead to 'chaos' and 'an Iraq on steroids.'

Graham urged Trump not to get out without a plan and said the goal of destroying IS militants in Syria had not yet been accomplished.

Trump stopped at the Dover Air Force Base to honor the four victims killed after a suicide bomber detonated explosives on Wednesday in Manbij, Syria

The attack took place after Trump announced he'd be pulling American troops from Syria

Aftermath of the deadly bomb in Manbij, Syria pictured above. It was the deadliest attack against Americans in Syria

Before Trump took off on Saturday, he briefly spoke with reporters, promising a speech at 4pm EST on the dragging government shutdown and border control.

He also shared some warning words for Pelosi from the White House lawn who he called 'controlled by the radical left'.

'I hope that Speaker Pelosi can come along and realize what everybody knows, no matter who it is, they know that walls work and we need walls. And whether it is personal or not, it is not personal for me,' he said Saturday morning.

'She's being controlled by the radical left which is a problem. She's under total control of the radical left. I think it is a very bad thing for her and very bad thing for the Democrats,' he added.

'Everybody knows that walls work. You look at different places, they put up a wall, no problem. You look at San Antonio, you look at so many different places, they go from one of the most unsafe cities in the country to one of the safest cities immediately,' Trump reiterated.

The government has been partially shut down for 29 days now, leaving hundreds of thousands of workers without pay.

Donald Trump said Speaker of the House Nancy Pelosi is 'controlled by the radical left' while briefly speaking to reporters Saturday morning

He told reporters he'll speak on border control and the Shutdown on Saturday adding 'I hope that Speaker Pelosi can come along and realize ... walls work and we need walls'

On Saturday Trump is expected to present a third spending bill proposal, as his last two have been rejected Pelosi, according to CNN.

Raising the stakes in his heated dispute with Pelosi, a Democrat from California, the president abruptly canceled her military flight on Thursday, just hours before she and a congressional delegation were scheduled to fly to Afghanistan on a previously undisclosed visit to U.S. troops.

On Friday she accused Trump of threatening her security when he publicly revealed her plans to head to Afghanistan.

'When the Speaker of the House and about 20 others from Capitol Hill decide to book their own commercial flights to Afghanistan, the world is going to find out,' a senior White House official said to DailyMail.com via e-mail. 'The idea we would leak anything that would put the safety and security of any American at risk is a flat out lie.'

Trump also tweeted directly at her saying: 'Why would Nancy Pelosi leave the Country with other Democrats on a seven day excursion when 800,000 great people are not getting paid.'