Washington (CNN) President Donald Trump spoke at length during a Cabinet meeting on Monday about his decision to withdraw US troops from northern Syria -- arguing that the US never agreed to protect Syrian Kurds forever, suggesting the US may secure an oil deal for the Kurds to bolster their finances and saying he's "the one that did the capturing" of ISIS fighters in Syria.

Earlier this month, the President decided to have the US exit northern Syria ahead of a Turkish incursion into the area. US troops were forced to leave former US allies -- the Kurds -- in the region, and last week the US negotiated a "ceasefire" with Turkey to have Kurds exit the area, a deal that forced America's one-time Kurdish allies to cede large swaths of territory to Turkey.

The President repeatedly said during the Cabinet meeting that a main reason behind his decision to have the US exit northern Syria was that it was something he campaigned on. He argued that though his stance was not popular in Washington, crowds at his rallies cheered loudly when he said he'd bring American troops home.

That includes American troops left "to secure the oil" as well as those in "the region where we've been asked by Israel and Jordan to leave a small number of troops."

Trump appeared to be referring to a small number of US forces located near Syria's oil fields as well as the US base at At Tanf in southern Syria which is located near the border with Jordan and is seen by many analysts see as a curb on Iran's influence in the region. The Trump administration had previously said that the At Tanf forces would remain despite the pullout from Syria. Secretary of Defense Mark Esper confirmed Monday that the forces near the oil fields would also remain for the time being and that they were not part of the current withdrawal phase.

Trump said he's advised for the US to "keep the oil" in Syria, adding that the US may strike an oil agreement with the Kurds.

"We want to keep the oil, and we'll work something out with the Kurds so that they have some money, have some cashflow. Maybe we'll have one of our big oil companies to go in and do it properly," he said.

Trump also took credit for "capturing" ISIS fighters in Syria, arguing that former President Barack Obama was not as successful.

"It was me and this administration working with others, including the Kurds, that captured all of these people that you're talking about right now," he continued. "It was done within a month and a half. So, I'm the one that did the capturing. I'm the one that knows more about it than you people or the fake pundits."

US 'never agreed to protect the Kurds'

Trump argued that though the US fought with Kurdish allies in northern Syria to defeat ISIS, the US "never agreed to protect the Kurds."

"We fought with them for three and a half to four years. We never agreed to protect the Kurds for the rest of their lives," he said, asking, "Where's an agreement that said we have to stay in the Middle East for the rest of humanity, for the rest of civilization to protect the Kurds?"

The Trump administration had previously convinced the Kurds to dismantle their defensive fortification and pull troops from the border to appease Turkey and stave off an invasion. The US also shared intelligence on the area with the Turkish military but Turkey opted to invade anyway.

The President also said Turkey's incursion into Syria targeting former US allies earlier this month was necessary.

"If shooting didn't start for a couple of days, I don't think the Kurds wouldn't have moved. I don't think, frankly, you would have been able to make a very easy deal with Turkey ... It was so nasty that when we went to Turkey and when we went to the Kurds, they agreed to do things that they never would have done before the shooting started," he added, emphasizing that if Kurds wouldn't have gone through "two and a half days of hell," "I don't think you would have been able to make a deal."

The 'ceasefire is absolutely holding'

Trump asserted that the "ceasefire is absolutely holding."

"There's some skirmishes, but very little, relatively speaking," he added.

However, his own defense secretary stated that he thinks "overall the ceasefire seems to be holding," despite "reports of intermittent fires."

"We see a stabilization of the lines if you will on the ground. And we do get reports of intermittent fires, this and that. That doesn't surprise me necessarily but that's what we're picking up, that's what we're seeing so far," Defense Secretary Mark Esper said Sunday.