(Adds comment from White House chief of staff)By Idrees Ali and Phil StewartWASHINGTON, Jan 28 (Reuters) - The Pentagon is evaluating a request from the U.S. Federal Emergency Management Agency (FEMA) to provide help in administering COVID-19 vaccines, a spokesman said on Thursday. "Given the significance of the request, it will be reviewed urgently but carefully to determine what DoD assets can safely be made available to support the effort," Pentagon spokesman John Kirby said in a statement. The Pentagon did not provide the number of troops that could be involved. At its peak under former President Donald Trump, more than 47,000 National Guard troops were supporting COVID-19 operations and about 20,000 continue to help. (Reporting by Idrees Ali and Phil Stewart, Editing by Dan Grebler and Peter Cooney)Our Standards: The Thomson Reuters Trust Principles.