who enters into any contract with the United States or any department or agency thereof either for the rendition of personal services or furnishing any material, supplies, or equipment to the United States or any department or agency thereof or for selling any land or building to the United States or any department or agency thereof, if payment for the performance of such contract or payment for such material, supplies, equipment, land, or building is to be made in whole or in part from funds appropriated by the Congress, at any time between the commencement of negotiations for and the later of (A) the completion of performance under; or (B) the termination of negotiations for, such contract or furnishing of material, supplies, equipment, land, or buildings, directly or indirectly to make any contribution of money or other things of value, or to promise expressly or impliedly to make any such contribution to any political party, committee, or candidate for public office or to any person for any political purpose or use; or

knowingly to solicit any such contribution from any such person for any such purpose during any such period.