WASHINGTON -- U.S. President Donald Trump is weighing the next iteration of his controversial travel ban, which could include new, more tailored restrictions on travellers from additional countries.

The Department of Homeland Security has recommended the president impose the new, targeted restrictions on foreign nationals from countries it says refuse to share sufficient information with the U.S. or haven't taken necessary security precautions. The restrictions could vary by country, officials said.

Trump's ban on visitors from six Muslim-majority nations, which sparked protests and a flurry of lawsuits, is set to expire this coming Sunday, 90 days after it took effect.

"The acting secretary has recommended actions that are tough and that are tailored, including restrictions and enhanced screening for certain countries," Miles Taylor, counsellor to acting Homeland Security Secretary Elaine Duke, told reporters on a conference call Friday.

But officials refused to say how many countries -- and which countries -- might be affected, insisting the president had yet to make a final decision on how to proceed. Trump huddled with Duke, Attorney General Jeff Sessions, Secretary of State Rex Tillerson, his director of national intelligence and his national security adviser Friday to discuss the issue, White House spokeswoman Lindsay Walters said.

Taylor said the recommendations were based on whether countries were providing U.S. authorities with enough information to validate the identities of potential immigrants and visitors and to determine whether or not they posed a threat. The recommendations were first reported by the Wall Street Journal on Friday.

Trump's travel ban executive orders remain two of the most controversial actions of his administration. The ban, which went into effect in late June, barred citizens of Iran, Libya, Somalia, Sudan, Syria and Yemen who lacked a "credible claim of a bona fide relationship with a person or entity in the United States" from entering the country. The Supreme Court is scheduled to hear oral arguments on the constitutionality of the ban next month.

Officials described the process of reaching the new recommendations as far more deliberate and systematic than Trump's original travel ban order, which was signed just days after he took office with little consultation or input outside the White House.

DHS said it had worked with other agencies to develop a comprehensive new baseline for foreign nationals based on factors like whether their countries issued passports with biometric information to prevent fraud and shared information about travellers' terror-related and criminal histories.

"Our guiding principle," Taylor said, "was this: We need to know who is coming into our country. We should be able to validate their identities, and we should be able to confirm that our foreign partners do have information suggesting such individuals may represent a threat to the United States."

The U.S. then shared the new baseline requirements with every foreign government in July and gave them 50 days to comply.

While most countries already met the standards, officials said that some that didn't have made changes that put them in compliance. Other countries, however, were unable or "deliberately unwilling" to comply. Citizens of those countries would be denied entry or face other travel restrictions until their governments made changes.

Trump had originally tried to ban the entry of nationals from seven Muslim-majority countries, including Iraq, in his January order, but scaled back his efforts in a more narrowly tailored version written to better withstand legal scrutiny in March. Trump later derided that second order on Twitter as "watered down" and "politically correct."

After a bomb partially exploded on a London subway last week, Trump once again called for a tougher ban.

"The travel ban into the United States should be far larger, tougher and more specific -- but stupidly, that would not be politically correct!" he wrote on Twitter.

The administration has argued the ban was necessary to give it time to complete a thorough review of screening procedures and information sharing to make sure that those who enter the country don't pose a safety risk.

Critics accuse the president of overstepping his authority and violating the Constitution's protections against religious bias by targeting Muslims. Trump had called for a "total and complete shutdown of Muslims entering the United States" during his campaign.

The American Civil Liberties Union, one of the groups challenging the ban in court, described the proposed changes as "an apparent effort to paper over the original sin of the Muslim ban."

"This looks to be the Trump administration's third try to make good on an unconstitutional campaign promise to ban Muslims from the United States," ACLU Executive Director Anthony D. Romero said in a statement.

A new travel policy could also complicate the Supreme Court's review, scheduled for argument on Oct. 10. The court could order the parties to submit written arguments about what should happen next, and it might dismiss the case or return it to lower courts for a fresh analysis of the changed circumstances.

Associated Press writer Mark Sherman contributed to this report.