President Donald Trump suggested on Saturday that he believes the controversial policy of family separations could continue in the United States and that the practice could dissuade immigrants from entering the country illegally.

Trump’s comments come on the heels of a Friday report in The Washington Post that the White House is actively considering plans that could again separate parents and children at the U.S.-Mexico border.

The newspaper, which cited several administration officials it did not name, reported that one option under consideration would detain asylum-seeking families together for up to 20 days and then give parents a choice of staying in family detention with their child as their immigration cases proceed or allowing children to be taken to a government shelter so other relatives or guardians could seek custody.

"We're looking at a lot of different things having to do with illegal immigration," Trump told reporters on the South Lawn of the White House.

"I will say this: If they feel there will be separation, they don't come," Trump said.

The practice of separating children from their parents at the border ignited a firestorm of criticism. Under pressure, Trump in June signed an executive order that said he said would end the practice and allow families to be detained together.

At least 2,600 children were separated from their parents under the Trump administration’s "zero tolerance" policy that called for prosecuting everyone who entered the country illegally. A federal judge ordered families to be reunified, and in September the government reported it had reunified or released 2,251 children.

The policy, in effect from May 6 through June 20, did not put a significant dent in the number of families crossing the border, according to data from U.S. Customs and Border Protection.

Trump has made illegal immigration a centerpiece of his campaign and presidency. On Saturday he insisted he wants workers to come into the country but repeated his refrain that he wants a “merit-based" immigration system and that he opposes the current lottery system.

A bill proposed by Republicans in August would halve the number of legal immigrants allowed into the United States while moving to a "merit-based" system of entry. Trump has said he supports that bill.

Asked if he would use immigration as a campaign issue for the midterm elections, in which Republicans are trying to maintain majority control in the House of Representatives and the Senate, Trump said "immigration is always tricky. But to me it's not tricky: You have to do the right thing, whether there's an election or not."

"I'm very tough at the borders, we’ve been very tough at the borders," Trump said. "People have to come into our country legally. Not illegally, legally. And I want them to come in on merit."

"If that's a bad policy, then guess what? A lot of bad things are going to happen. But a lot of people agree with me,” he said.

The Post reported that family separation plans under consideration by the White House do not include a repeat of the administration's actions earlier this year, which were described as chaotic.

Among the critics of those border separations was Trump's daughter and White House adviser, Ivanka Trump. In August she called the family separations a "low point" for her father’s administration.

"That was a low point for me as well," she said. "I feel very strongly about that, and I am very vehemently against family separation and the separation of parents and children."