Protesters gather at the US Customs and Border Protection offices in Washington, D.C., March 7, 2017, to oppose the rollout of the revised travel ban by President Trump. (Astrid Riecken)

A federal judge in Washington on Thursday signaled her willingness to become the third judge nationwide, if needed, to order a halt to President Trump’s revised executive order banning new visas and immigration from six Muslim-majority countries.

U.S. District Judge Tanya S. Chutkan postponed ruling on two combined challenges to the White House action by Iranian-American organizations and a Shi’a Muslim group, saying she would wait for decisions expected after federal appeals courts arguments this month on halts imposed March 15 by judges from Hawaii and Maryland.

But Chutkan said she was persuaded by arguments that the groups’ missions and the lives of more than a dozen individual plaintiffs would be unconstitutionally harmed by the travel ban.

“Upon consideration of the parties’ submissions, the court is inclined to agree with Plaintiffs that they are likely to succeed on the merits of their claims. However … The existence of two other nationwide injunctions temporarily casts uncertainty on the issue of whether the harms Plaintiffs allege are actually imminent or certain,” Chutkan wrote in a two-page order that did not delve into the arguments.

A 13-judge panel of the U.S. Court of Appeals for the 4th Circuit in Richmond is expected to issue a ruling after becoming the first appellate court to hear arguments on the question Monday. Arguments before a three-judge panel of the 9th Circuit in San Francisco are set for May 15, Chutkan noted.

She concluded: “In the event that both existing injunctions are overturned, this court is prepared to issue a ruling without delay.”

Spokesmen for the suing Iranian American groups — Pars Equality Center, the Iranian American Bar Association, National Iranian American Council, and Public Affairs Alliance of Iranian Americans — and the Shi’a group, Universal Muslim Association of America, did not immediately respond to requests for comment.

Johnathan Smith, legal director of Muslim Advocates, one of the plaintiffs said in a statement that “this court recognized that the plaintiffs are likely to succeed on the merits of their claim. In so doing, this court, like many others, has sided with religious liberty and dignity. The plaintiffs here have had their most basic rights trampled on by the Trump Administration, and we will continue to do all that we can to ensure that they receive the justice they deserve.”

A spokeswoman for the Justice Department said it declined to comment on the pending litigation.

The case before Chutkan came on behalf of the largest ethnic group directly affected by the March 6 executive order, and is one of a half-dozen ongoing challenges to the White House action watched closely by legal analysts.

Chutkan allowed live testimony last month by leaders of the groups, whose lawyers said they hoped the detailed declarations and statements from American immigrants from the Middle East’s most populous nation will bolster the legal standing of ban opponents in a fight widely seen as destined for the U.S. Supreme Court.

More Iranians received U.S. visas in 2015 than nationals from the other five countries on the list combined — Libya, Somalia, Sudan, Syria and Libya — or 57 percent of the total including Iraq, which was on an initial travel ban list but dropped in the revised ban. Iranian students accounted for about 80 percent of foreign students last year from the same countries, U.S. data show.