Sept 14 (Reuters) - Wells Fargo & Co (WFC.N) on Tuesday pushed back the date when its employees return to office in the United States to the beginning of November, according to a memo seen by Reuters. Wells Fargo"s operations and contact center employees will start returning to office over several weeks beginning Nov. 1, followed by business support and enterprise functions in December, according to the memo. The bank had earlier pushed its return to office start date to Oct. 18 from Sept. 6 because of an increased risk from the Delta variant. read more The change to Nov. 1 comes days after U.S. President Joe Biden announced new mandates requiring most federal employees to get COVID-19 vaccinations and pushing large employers to have their workers inoculated or tested weekly. "We are studying these proposed requirements to better understand how they apply to our RTO (return to office) plans, and will share more information when it is available," Wells Fargo said in the memo.