No, you do not need to report or pay tax on a cash gift received from a non-US citizen as long as the gifts do not exceed the threshold for reporting (aggregate amount greater than $100,000).
From the IRS article on Large Gifts or Bequests from Foreign Persons:
You are required to report the receipt of foreign gifts or bequests only if the applicable thresholds apply. For purposes of determining the reporting thresholds, you must aggregate gifts received from related parties. See the instructions to Part IV of Form 3520 for more information; see also Section VI of Notice 97-34 PDF.
- For gifts or bequests from a nonresident alien or foreign estate, you are required to report the receipt of such gifts or bequests only if the aggregate amount received from that nonresident alien or foreign estate exceeds $100,000 during the taxable year. If the gifts or bequests exceed $100,000, you must separately identify each gift in excess of $5,000.
