Washington (CNN) President Donald Trump's announcement on "Fox and Friends" Friday morning that Tom Homan would be his new "border czar" appears to have been premature.

Homan, a Fox News contributor, was caught by surprise by the announcement, according to a source familiar.

Two senior White House officials acknowledged the details of a position are still being worked out and conversations are ongoing.

Trump's announcement also caught officials within the White House by surprise. Talks about the nature of the border czar position are still ongoing, according to one of the officials. Prior to the President's announcement, aides had not finalized the nature and scope of the role and they had not formally vetted candidates, though Homan's name has been floated internally.

Among the potential problems associated with the czar role is structuring it in a way that does not run afoul of the statutory responsibility given to the Department of Homeland Security when it was created by Congress. According to this official, those decisions are still not settled, even after Trump made his announcement this morning.

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