Rubio announced that Riley Barnes, the assistant secretary of state for democracy, human rights and labor, would serve as US special coordinator for Tibetan issues.

"The United States remains committed to supporting the unalienable rights of Tibetans and their distinct linguistic, cultural and religious heritage," Rubio said in a message for Losar, the Tibetan new year.

A top priority for US policymakers in recent years has been to defend Tibetan religious rituals in selecting a reincarnation for the Dalai Lama, fearing that China will seek to identify and groom a compliant successor to the charismatic 90-year-old, who has used his global stature to advocate greater rights for Tibetans.

The special coordinator position is required by an act of Congress passed in 2002. Successive administrations have designated senior officials to serve concurrently in the role, although President Donald Trump in his first term waited months before leaving to make an appointment.

Rubio as a senator was known for his staunch advocacy of human rights in China, leading an effort to support the Uyghur minority with a law that banned imports from the Xinjiang region unless they were certified not to involve forced labor.

Since becoming the top US diplomat, Rubio has joined the Trump administration in narrowing the focus on human rights, using the issue as a cudgel against adversaries while mostly refraining from criticizing Trump's partners.

Trump has focused heavily on trade in his relationship with China, which he plans to visit in April.

Rubio, speaking Monday in Hungary, noted that China has the second largest economy and nuclear weapons and said it would be "insane for United States and China not to have relations and interact with one another."