Aug 10 (Reuters) - Citigroup Inc (C.N) will require U.S. employees returning to its New York headquarters and offices in some cities to be vaccinated against COVID-19, the bank"s head of human resources, Sara Wechter, said in a LinkedIn post on Tuesday. The bank expects these employees to start returning to the office for at least two days a week starting Sept. 13, the post said. The bank"s decision would also affect employees in the Chicago, Boston, Philadelphia and D.C. offices. The bank will also be providing rapid test kits for its employees. These employees will be required to wear masks given fears around the highly transmissible Delta variant of the coronavirus. For employees at other branches, Citigroup would "strongly encourage", but not mandate vaccination. Wall Street remains divided over postponing back-to-office plans due to the Delta variant. Some major firms including Wells Fargo & Co (WFC.N) and BlackRock Inc (BLK.N) have delayed their return plans, while others including Bank of America Corp (BAC.N) and Morgan Stanley (MS.N) have stuck to the previous guidance. read more