WASHINGTON (REUTERS) - Former US Secretary of State Hillary Clinton may have violated federal records laws by using a personal e-mail account for all of her work messages, the New York Times reported on Monday.

The newspaper said the likely Democratic presidential candidate conducted all her official business during her four-year tenure at the State Department on a private e-mail account.

It added that Clinton, who stepped down as secretary of state in 2013, recently handed over 55,000 pages of e-mails to the State Department in response to a department effort to comply with record-keeping practices.

Federal law says letters and e-mails written and received by federal officials are government records that must be retained, according to the paper. Regulations at the time Clinton served as secretary of state called for e-mails on personal accounts to be preserved as well, the paper said.

The Times said most experts believed private e-mail accounts should only be used for official government business in emergencies, according to the Times.

A spokesman for Clinton told the Times that Clinton was complying with the "letter and spirit of the rules" and had expected her e-mails would be retained. He declined to detail why she chose to conduct business from her personal account, the Times said.

The State Department did not immediately return a request for comment from Reuters. Clinton's spokesman could also not be immediately reached for comment.

Clinton is widely considered the front-runner for next year's Democratic presidential nomination if she decides to enter the race.