Posted : 2021-05-05 09:28 Updated : 2021-05-05 09:28 In this file photo taken on Feb. 5, U.S. Secretary of the Treasury Janet Yellen listens while U.S. President Joe Biden speaks about COVID-19 relief from the State Dining Room of the White House in Washington, DC. AFP-Yonhap European and US equity markets mostly fell Tuesday, with the Nasdaq slumping on valuation concerns after US Treasury Secretary Janet Yellen said interest rates could rise. Yellen, in a pre-recorded conversation with The Atlantic, said US lending rates may have to increase "somewhat" to keep a lid on inflation if President Joe Biden's latest spending proposals are enacted and the economy heats up.