WASHINGTON, July 9 (Reuters) - U.S. Treasury Secretary Janet Yellen on Tuesday, asked whether she had seen any evidence of mental or cognitive decline in President Joe Biden, said the president was extremely effective in meetings in which she participated.

Yellen told members of the House Financial Services she was not aware of any discussions among cabinet secretaries on invoking the 25th amendment to the U.S. Constitution, which enables the vice president and cabinet members to declare the president is unable to discharge the powers and duties of the office, transferring the job to the vice president.

"The president is extremely effective in the meetings that I've been in with him," Yellen told the committee. She declined to say when she last met with him in person. (Reporting by David Lawder and Andrea Shalal, Editing by Franklin Paul)