The World Cup referee who was denied entry into the United States "was talking to some very bad people," said Andrew Giuliani, chief of the White House task force for soccer's biggest tournament.

Omar Artan was going to be the first referee from Somalia to officiate at a World Cup. But he was denied entry at Miami International Airport on Saturday over "vetting concerns," U.S. Customs and Border Protection said in a statement without providing details.

Artan was issued a visa to travel to the U.S. last week, according to the Somali Embassy in Kenya, which processed it.

"Very simply, the president has created many pathways for players, coaches, fans to be able to come in the country. Look, every single player has received access to the United States that's applied, every coach that's received access," Giuliani, the son of former New York Mayor Rudy Giuliani, told CBS News on Sunday.

"There will be a few officials. … In the case of the referee there, he was talking to some very bad people right as he was coming to the United States, and there's some classified information we can't discuss now," he said.

"At some point, that may be released, but what I can tell you is it was the right decision by CBP. It was the right decision by the secretary of homeland security, and I stand by that decision."

Giuliani added that Artan's communications with "bad people" were "happening before he was coming to the United States of America."

"It was not a few years before. This was immediately before he was coming to the United States," he said.

Somalia is one of 39 countries listed in an executive order signed last year by President Donald Trump that bars or restricts the entry of foreign nationals on national security grounds.

FIFA said it played no role in Artan's denial of entry and shared a statement on his behalf saying he was in "a positive mood" and "focused on the next challenges" in his refereeing career, according to CBS News.

Artan returned to a hero's welcome in Somalia, with cheering fans and supporters at Mogadishu's airport. He vowed to attend the next World Cup and urged Somalis "to take comfort in this and remain confident."