WATCH: Jen Psaki talks on halting of Afghan flights, Xi call

The U.S. has halted all U.S.-bound flights of Afghan evacuees from two main bases overseas after discovering a limited measles outbreak among Afghans arriving in the United States, a hitch that American officials warned will have a severe impact on an often-troubled U.S.-run evacuation.

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U.S. Customs and Border Protection made the decision on the recommendation of the Centers for Disease Control and Prevention to halt the flights from U.S. bases in Germany and Qatar, according to a U.S. government document seen Friday by The Associated Press. The document cited unspecified “health safety concerns.”

White House press secretary Jen Psaki said the temporary halt stemmed from discovery of measles among four arrivals in the United States.

The government document viewed by the AP said the halt would “severely impact” operations at Ramstein Air Base in Germany and have an “adverse effect” on the nearly 10,000 evacuees, many of whom it said have been there more than 10 days and are increasingly fatigued.

The halting of the flights is a problem for the United States in part because many of the evacuees already have been at the Ramstein base longer than the 10-day limit Germany set in allowing the U.S. to use the country as a transit site.

Psaki also commented on President Biden’s call Thursday with Chinese President Xi Jinping amid growing frustration on the American side that high-level engagement between the two leaders’ top advisers has been largely unfruitful.

Biden initiated the call with Xi, the second between the two leaders since Biden took office.

Psaki said the conversation “was about keeping the channels of communication open” and “engaging Xi directly at the leader level due to the centralization of power and the power that’s in his hands.”

She declined to detail the range of topics discussed but said Biden and Xi covered “a range of transnational issues, including including COVID-19.”