At least two of the president’s top economic advisers, Heather Boushey and David Kamin, have privately expressed reservations about the size of the checks and at what level they would begin to phase out for higher-income people, according to three people familiar with internal discussions.

The aides worry that the checks will cost so much that there won’t be enough left over in Biden’s proposed pandemic relief bill for other priorities — supplemental unemployment benefits, an expanded child tax credit, or aid to states and local governments, the people said.

Neither Boushey, who sits on the Council of Economic Advisers, or Kamin, a deputy director of the National Economic Council, responded to requests for comment.

Outside the White House, a group of 10 GOP Senators offered a $600 billion stimulus counterproposal on Sunday that includes $1,000 checks with strict income requirements. Their plan is less than a third the size of Biden’s.