Former Secretary of State Colin Powell said Friday he once sent Hillary Clinton a memo touting his use of a personal email account for work-related messages after she took over as the nation’s top diplomat in 2009.

In a statement provided to The Associated Press, Powell said he emailed Clinton describing his use of a personal AOL account for unclassified messages while leading the State Department under President George W. Bush. Powell said he told Clinton his use of personal email “vastly improved” communications within the department, which at the time did not have an equivalent internal system.

Powell said the FBI may have obtained a copy of his memo to Clinton during its year-long investigation into Clinton’s use of a private email server to handle sensitive information during her time as secretary. The FBI closed its investigation last month without finding evidence to support criminal charges against the Democratic presidential nominee.

Powell, a retired Army general and former chairman of the Joint Chiefs of Staff, said he used a secure computer on his desk at the State Department to manage classified information.

Unlike Clinton, Powell relied on a commercially available service to host his personal email account. Clinton’s private server was located in the basement of the New York home she shared with her husband, former President Bill Clinton.

Powell issued the statement after veteran political journalist Joe Conason released an excerpt from his upcoming book about Bill Clinton that recounts a 2009 dinner party for Hillary Clinton hosted by former Secretary of State Madeleine Albright. Powell was in attendance, along with other former secretaries including Henry Kissinger and Condoleezza Rice.

During dessert, Powell advised Clinton to use a personal email account while in office, as he had done, according to the passage from the book “Man of the World: The Further Endeavors of Bill Clinton” provided to AP. Powell reportedly told Clinton that his use of personal email to communicate with his staff had been “transformative for the department.”

According to Conason’s retelling, Clinton replied that she had already decided to continue using the private server in her home she had relied on during her 2008 presidential bid.

In his statement, Powell said he has “no recollection” of his purported dinner conversation with Clinton.