United Airlines CEO Oscar Munoz has staked out a hardline position on alleged Gulf airline subsidies, warning of a “huge uproar from Americans” when the full scope of the issue becomes widely known and US jobs are potentially lost.

Speaking March 2 at the US Chamber of Commerce Aviation Summit in Washington DC, Munoz made clear that he and United will aggressively push the US government to take action against the United Arab Emirates (UAE) and Qatar over what Munoz considers to be completely unacceptable government assistance to Emirates Airline, Etihad Airways and Qatar Airways.

“Those airlines aren’t airlines. They’re international branding vehicles for their countries,” Munoz told reporters on the sidelines of the conference.

United and fellow US majors American Airlines and Delta Air Lines in 2015 accused Qatar Airways and UAE carriers Emirates and Etihad of getting more than $40 billion of subsidies from their government owners, providing the Gulf airlines with what the US airlines view as an unfair advantage as the Middle East carriers expand flights to the US.

Munoz, who became United CEO in September 2015, was not in the airline industry when the accusations were made. But he indicated United will not be backing off at all from predecessor Jeff Smisek’s stance on the Gulf carrier issue, and his comments at the Chamber of Commerce event were markedly pointed.

“Facts tend to overcome a lot of emotion,” he told the audience at the event, explaining that the “order of magnitude” of the alleged subsidies, “even if you cut them in half,” go beyond “anything I’ve seen before.”

Munoz alleged that some of the Gulf carriers’ flights to the US are landing with “20 or 30 people” on board, which he said is a sign of those airlines being “heavily subsidized.”

US airline employees “have been to hell and back” and deserve a level playing field with international airlines, he said.

When asked by reporters about Norwegian Air International, another international competitor to US carriers that has been a source of controversy, Munoz said, “Norwegian is being clever … That we can compete with. The [Gulf carriers], we can’t.”