U.S. President Joe Biden was sending a delegation of former senior defense and security officials to Taiwan on Monday, a senior official of his administration said, a sign of support for the island claimed by China after Russia's invasion of Ukraine.

The visit, led by one-time chairman of the Joint Chiefs of Staff Mike Mullen, comes at a time when Taiwan has stepped up its alert level, wary of China taking advantage of a distracted West to move against it.

Beijing claims the democratically governed island as its own and has vowed to bring it under Chinese control, by force if necessary.