President Donald Trump praised his new chief of staff on Monday as a skilled fixer who has dramatically slowed illegal immigration at the U.S-Mexico border.

'We all know him. We respect him. I admire what he's done,' Trump said of retired general John Kelly, who was secretary of Homeland Security until Friday.

The president told reporters at the beginning of a cabinet meeting that he has 'no doubt that he will be an absolutely superb chief of staff.'

'At Homeland [Security] what he has done has been nothing short of miraculous,' he said. 'As you know, the border was a tremendous problem. And now, close to 80 per cent stoppage.'

'I predict that General Kelly will go down, in terms of the position of chief of staff, one of the great[est] ever,' Trump added.

The president insisted Monday that Kelly wasn't inheriting a White House in chaos, citing policy achievements but not addressing his personnel shakeups, a failed push to repeal Obamacare or an ongoing feud with his attorney general.

President Donald Trump praised his new White House chief of staff John Kelly on Monday, saying at the beginning of a cabinet meeting that the retired general would be a 'superb' addition to the West Wing

Monday's cabinet meeting was the first for Kelly as a White house aide; he previously attended as secretary of Homeland Security. Kelly is seen at the end of the Cabinet Room table to the right of the doorway

'Highest Stock Market EVER, best economic numbers in years, unemployment lowest in 17 years, wages raising, border secure, S.C. [Supreme Court]: No WH chaos!' the president tweeted.

An hour later in the Oval Office, Trump said his administration 'has done very well' and set 'lots of records.'

'We’re doing very well. We have a tremendous base,' the president told reporters as he posed for pictures with new White House Chief of Staff John Kelly, a retired army general. 'The country is optimistic. And I think the general will just add to it.'

Reince Priebus was handed his walking papers on Friday, departing after just six months as chief of staff.

Just days earlier Trump's press secretary Sean Spicer quit in a huff over the hiring of Trump friend Anthony Scaramucci as communications director.

Scaramucci proceeded to go on an expletive-filled tirade against Priebus and White House chief strategist Steve Bannon, memorialized by a New Yorker reporter.

OUT WITH THE OLD ... Reince Priebus was handed his walking papers on Friday, capping off a tumultuous week at the White House

IN WITH THE NEW ... Trump welcomed his new chief of staff on Monday, posing with Kelly in the Oval Office

Despite a staff shakeup, an Obamacare repeal debacle, internal staff feuds and an ongoing tiff with his attorney general, Trump insisted Monday that his White House isn't a hotbed of chaos

What may have been Trump's worst week in office was capped off by a drawn-out failure to repeal the Obamacare medical insurance law, coming via a stunning one-vote defeat in the Senate.

Newly minted chief of staff John Kelly, a retired four-star general who was previously secretary of Homeland Security, is expected to bring discipline and focus to the West Wing.

His old job could soon be filled by shifting Jeff Sessions over from the Department of Justice.

Trump began last week by bashing Sessions, saying he was 'disappointed' in his now months-old decision to recuse himself from the DOJ's ongoing Russia probe.

Kelly's success in a chaotic White House will depend on how much authority he is granted and whether Trump's dueling aides will put aside their rivalries to work together. Also unclear is whether a new chief of staff will have any influence over the president's social media histrionics.

White House Communications Director Anthony Scaramucci added to Trump's tumult last week by ging on an expletive-filled rant against two senior West Wing staffers

The White House is still reeling from the Senate's failure to pass an Obamacare repeal, which was scuttled by Sen. John McCain (standing, at left)

Former Trump campaign manager Cory Lewandowski, who was ousted from the campaign in June 2016, said on NBC's 'Meet the Press' that he expected Kelly would 'restore order to the staff' but also stressed that Trump was unlikely to change his style.

'I say you have to let Trump be Trump. That is what has made him successful over the last 30 years. That is what the American people voted for,' Lewandowski said. 'And anybody who thinks they're going to change Donald Trump doesn't know Donald Trump.'

Kelly's start follows a tumultuous week, marked by a profane tirade from the new communications director, Trump's continued attacks on his attorney general and the failed effort by Senate Republicans to overhaul the nation's health care law.

In addition to strain in the West Wing and with Congress, Kelly starts his new job as tensions escalate with North Korea.

The United States flew two supersonic bombers over the Korean Peninsula on Sunday in a show of force against North Korea, following the country's latest intercontinental ballistic missile test. The U.S. also said it conducted a successful test of a missile defense system located in Alaska.

California Democratic Sen. Dianne Feinstein said on CBS' 'Face the Nation' that she hopes Kelly can 'be effective,' and 'begin some very serious negotiation with the North and stop this program.'

Trump tweeted on Saturday about his disappointments, particularly with China and its lack of action on the matter of North Korea

Another diplomatic fissure opened Sunday when Russian President Vladimir Putin said the U.S. would have to cut its embassy and consulate staff in Russia by several hundred under new sanctions from Moscow. In a television interview, Putin indicated the cutback was retaliation for new sanctions in a bill passed by Congress and sent to Trump.

Trump plans to sign the measure into law, the White House has said. After Putin's remarks, the State Department deemed the cutbacks 'a regrettable and uncalled for act' and said officials would assess the impact and how to respond to it.

While Trump is trying to refresh his team, he signaled that he does not want to give up the fight on health care. On Twitter Sunday, he said: 'Don't give up Republican Senators, the World is watching: Repeal & Replace.'

The protracted health care fight has slowed Trump's other policy goals, including a tax overhaul and infrastructure investment.

But Trump aides made clear that the president still wanted to see action on health care. White House budget director Mick Mulvaney said on CNN's 'State of the Union,' that senators 'need to stay, they need to work, they need to pass something.'

Asked if nothing should be voted on in Congress until the Senate votes again on health care, Mulvaney said: 'well, think - yes. And I think what you're seeing there is the president simply reflecting the mood of the people.'

On Saturday, Trump threatened to end required payments to insurance companies unless lawmakers repeal and replace the Obama-era health care law. He tweeted that if 'a new HealthCare Bill is not approved quickly, BAILOUTS for Insurance Companies and BAILOUTS for Members of Congress will end very soon!'

The payments reduce deductibles and co-payments for consumers with modest incomes. Trump has guaranteed the payments through July, but has not made a commitment going forward.

White House counselor Kellyanne Conway said on 'Fox News Sunday' that Trump would make a decision on the payments this week.

Maine Republican Sen. Susan Collins, who opposed the efforts to move an Obamacare repeal bill forward this week, said on CNN that cutting the payments would 'be detrimental to some of the most vulnerable citizens' and that the threat has 'contributed to the instability in the insurance market.'

The House has begun a five-week recess, while the Senate is scheduled to work two more weeks before a summer break.