US presidential candidate Hillary Clinton laughs during a roundtable campaign event with small businesses in Cedar Falls, Iowa, United States, yesterday. Photo: Jim Young/Reuters

A federal judge yesterday ordered the US State Department to produce a schedule for the release of e-mails that Hillary Clinton sent and received while she was secretary of state, a legal move that could complicate her presidential campaign.

A lawyer in the case, Jeffrey Light, told Reuters that US District Judge Rudolph Contreras ordered the State Department to come up with a timetable by next week for the rolling release of the 55,000 pages of e-mails.

The judge also told the State Department to come up with a schedule by next week for releasing 300 Clinton e-mails related to US operations in Benghazi, Libya where four American officials, including the US ambassador to Libya, were killed in a September 11, 2012 attack, Light said.

Clinton, the front-runner for the 2016 Democratic presidential nomination, has come under criticism for storing and sending emails related to her official duties via a private server based in her house in New York state. She has now turned over the messages to the State Department.

Republican foes have accused Clinton of secretive practices by using a personal email server for messages she sent and received as America’s top diplomat. The Republicans want the e-mails to be released soon.

The State Department had proposed a mid-January deadline to finish a review and release Clinton’s work e-mails from her time as secretary of state, a post she held between 2009 and 2013.

Clinton has said she thought it simpler to have one e-mail account so she would only need to carry one handheld e-mail device. She has also said that while she should have used a separate government e-mail account, she violated no rules.