外国人在美国的房产, 属于 US situs property, 应该是要 subject to US gift tax 的.
What is U.S. Situs Property for Estate and Gift Tax Purposes? If an individual is deemed to be a NRA, then he would be subject to U.S. estate and gift tax only on his U.S. situs property. What is considered U.S. situs property varies depending on the estate or gift tax regime. Below is a chart summarizing certain assets that are commonly held by a NRA.