The firm hired by the MBTA pension fund’s board to conduct an independent review of the fund’s financial and investment records is interviewing staff and seeking a copy of a critical report coauthored by Wall Street whistle-blower Harry Markopolos, according to a letter obtained by the Globe.

FTI Consulting Inc. was hired in December in response to a report last summer that the $1.6 billionpension fund may be overstating its assets by as much as $470 million.

According to a Jan. 29 letter to Markopolos, FTI is interviewing ­relevant pension staff, management, and providers of services to the ­retirement fund.

The firm is also looking to get a copy of the report by Markopolos and Boston University finance professor Mark Williams, and to speak with them.

John Sullivan, a senior managing director in FTI’s Forensic Litigation Consulting group, asked Markopolos in the letter if he could speak with him by Feb. 19.

Markopolos and Williams in June presented their findings to the FBI, the Securities and Exchange Commission, and other authorities. The authors have so far declined to provide the report to MBTA pension officials, so as not to hamper any regulatory investigations.

Under Massachusetts law, the pension fund is organized as a ­private trust and is not required to follow the disclosure or ethics rules of other funds for public workers. The pension board does not hold public meetings, and trustees have long been discouraged from talking to reporters, including three new members appointed by Governor Charlie Baker.

A spokesman for the fund, Steve Crawford, in a statement said: “FTI was hired by the Board of Trustees to conduct a thorough and independent review. The review began in December and is expected to be completed in February. The fund’s management and staff are cooperating fully.’’

A spokeswoman for FTI did not respond Monday to a request for comment.

The release of the pension fund’s 2014 annual report — 13 months after the end of the reporting period — has been delayed while the internal review is conducted.

Beth Healy can be reached at beth.healy@globe.com. Follow her on Twitter @HealyBeth.