The Trump administration has "what we need" when it comes to funding for the conflict in Iran, National Economic Council Director Kevin Hassett told CBS News' "Face the Nation" on Sunday.

"Whether we have to go back to Congress for more is something that I think that [Office of Management and Budget Director] Russ Vought and OMB will look into. But the latest number I was briefed on was $12 billion [that has already been spent on the war]."

Hassett added that "this is something that we've got the weapons that we've already got in place to do this. And so we are not necessarily going to need any kind of supplemental."

Last week, House Speaker Mike Johnson said an Iran conflict supplemental funding package was "inevitable," The Hill reported.

The Louisiana Republican said "we don't yet know what the details of that will be. As you know, in the process submitted by the administration and Congress, and then it's deliberated upon en masse, we were anticipating a supplemental even before the Iran operation began. So that will happen. The timetable is yet to be determined."

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