Sen. Ted Cruz (R-Texas) introduced legislation Tuesday aimed at preventing “known terrorists” from entering the U.S. to serve as U.N. envoys in New York.

“It is unconscionable that, in the name of international diplomatic protocol, the United States would be forced to host a foreign national who showed a brutal disregard for the status of our diplomats when they were stationed in his country,” Cruz told the Senate.

The move comes several months after Iranian President Hasan Rouhani nominated a diplomat named Hamid Aboutalebi as Iran’s next representative to the U.N. in New York and filed a visa application.

Aboutalebi allegedly belonged to a group of student radicals loyal to Ayatollah Ruhollah Khomeini who seized the U.S. Embassy in Tehran after the Islamic revolution, and held 52 Americans hostage for 444 days in 1979-1981.

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