WASHINGTON -- The U.S. government has provided some clarity: Canadian passport-holders have the right to travel to the United States, despite days of confusing, contradictory messages about Donald Trump's travel restrictions.

Four days after the order was announced, the American administration held its first detailed news conference Tuesday shedding light on who can still travel to the U.S. and who can't -- at least not until the order is reviewed in a few months.

The U.S. government confirmed publicly what it has privately told the Canadian government: that citizens of non-affected countries, including dual citizens, are exempt by the travel freeze on seven majority-Muslim countries.

It was a relevant question for about 35,000 Canadians. That's how many have dual citizenship with the seven affected countries, and some of those Canadians may have jobs, families, and homes in the U.S.

"Travellers will be assessed at our border based on the passport they present -- not any dual national status. So if you're a citizen of the United Kingdom, you present your United Kingdom passport," said Kevin McAleenan, acting commissioner of the U.S. Customs and Border Protection agency.

"The executive order does not apply to you."

He made those remarks next to his boss, Homeland Security Secretary John Kelly. The newly named cabinet secretary said the order will be followed humanely.

Early accounts were laden with confusion.

The State Department stated that it applied to dual citizens. Some officials suggested it might also ban permanent U.S. residents. Those mixed messages sowed concern around the globe.

Airports were hit with protests, as hundreds of travellers were detained. McAleenan said about 721 travellers were denied the right to board planes among the 500,000 non-Americans travelling to the U.S.

The order still applies to temporary visitors with visas. Visa holders will be denied the right to board flights to the U.S., and sent to State Department representatives for additional instruction.

The order could be temporary, and will be reviewed in several months.

Kelly pushed back at reports that he and other officials were frozen out of the drafting of the order, and that the process was led by highly partisan staff around Trump without legal or national-security qualifications.

Kelly said he saw two early drafts of the order. In recent days, he said, staffers kept him informed of changes.

"I relied on people... to say, 'Okay, we've got it, boss... this looks good to us,' and we're off to the races," Kelly said.

"I did not look at it from the perspective of... correcting the grammar or saying, you know, we need to change these words or do this thing. People that know the immigration process infinitely better than I do... were the ones that did the staff work."