WASHINGTON — (CNN) The State Department is releasing fewer of former Secretary of State Hillary Clinton’s emails than required this month, falling behind schedule as they near their final production deadline.

“We have worked diligently to come as close to the goal as possible, but with the large number of documents involved and the holiday schedule we have not met the goal this month,” the State Department said in a statement to reporters Thursday morning.

The State Department was supposed to release over 8,000 pages of emails Thursday — 16% of Clinton’s total available emails — but will be releasing approximately 5,500 instead.

Additional emails will be released “sometime next week,” according to the statement.

The State Department was ordered to release all of Clinton’s work-related emails by Judge Rudolph Contreras as part of a Freedom of Information Act lawsuit brought by journalist Jason Leopold. The case came after it was revealed that Clinton used a private email server to conduct official business while leading the department.

In May, Contreras ordered the State Department to “aspire to abide” to a monthly production schedule, releasing specified numbers of emails at the end of each month up until January 29, 2016.

While the schedule is aspirational, the department must also submit reports each month to explain its progress. State Department attorneys will therefore have to explain the failure to meet the December quota in a filing to Contreras next week.

The 5,500 pages of documents will be made publicly available Thursday at approximately 4 p.m. ET.

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