He delivered the comments during a cabinet meeting at the White House on Tuesday afternoon, the 12th day of the partial shutdown.
He also weighed in on other issues, including Syria and Mitt Romney.
Here’s a quick look at some of what was said.
On the government shutdown
Trump said the partial shutdown of the government, which was triggered by an impasse over funding for his Mexico border wall, will last “as long as it takes.”
“Could be a long time or could be quickly,” Trump said.
The president said Homeland Security officials will plead for the border wall during a border security briefing for congressional leaders.
Afterward, there was no indication that any progress was made, however. House Republican Leader Kevin McCarthy later said that leaders were asked to return on Friday.
On the border (and drones)
As part of an argument for the border wall, Trump suggested other measures to curb the number of migrants crossing the border were “bells and whistles.”
“I know more about drones than anybody. I know about every form of safety that you can have,” he said. “And it’s all good but it’s just very minor compared to the power of a wall.”
He described the U.S. border with Mexico, where the entry of a wave of migrants has triggered strong political and humanitarian reaction, as “like a sieve.”
WATCH: Donald Trump: I know more about drones than anybody
On North Korea
Trump said the U.S. is making some inroads with North Korea, showing off a letter from leader Kim Jong Un. He said the two parties would like to meet for a second time.
“We’ve established a very good relationship. We’re given no credit for it,” he said.
“Frankly, if this administration didn’t take place … you’d be at war right now. You’d be having a nice big fat war in Asia.”
WATCH: Trump shows off letter from Kim Jong Un, says relationship is ‘strong’
Trump has not committed to a timeline on the U.S. withdrawal from war-torn Syria, which was announced late last month.
He said troops would leave “over a period of time,” adding that he wants to protect the U.S.-backed Kurdish fighters in the country as Washington draws down troops.
WATCH: Donald Trump gives no timetable for withdrawal from Syria
On Mitt Romney
Trump also weighed in on recent criticism from former presidential nominee Mitt Romney.
“I think that Mitt Romney hopefully will be a team player, but if not, that’s OK too,” Trump said. “Look, I handle it.”
With files from Reuters and the Associated Press