Story highlights McMaster worked closely with the Iraqi man during Battle of Tal Afar

He replaced Michael Flynn as Trump's national security adviser

(CNN) H.R. McMaster, President Donald Trump's new national security adviser, spoke at a naturalization ceremony in Alexandria, Virginia, earlier this month where an Iraqi family he sponsored became US citizens, an administration official tells CNN.

McMaster worked closely with the Iraqi man during Battle of Tal Afar in northern Iraq in 2005, the official said, and subsequently sponsored his family to immigrate to the United States and become citizens. The family invited the Army lieutenant general to the event, where he was asked to give brief remarks, the official added.

McMasters' attendance at the naturalization ceremony comes in the midst of the Trump administration's crackdown on refugee travel and weeks after the White House tried to ban immigration temporarily from seven Muslim-majority countries, including Iraq.

That attempt was thwarted by court rulings, but on Monday, the White House rolled out a second attempt at a travel ban. This time, though, it notably left Iraq off the list of banned countries.

Secretary of State Rex Tillerson said Monday that Iraq was removed from the list after assurances about stricter screening were given from the Iraqi government.

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