The University of Delaware library is in possession of nearly 2,000 boxes of archival records covering Joe Biden's 36 years as a senator but has not committed to releasing them before the presidential election, which the former vice president is expected to enter on Thursday.

The records were donated by Biden to his alma mater during his first term as vice president in 2011. Biden stipulated when he donated the papers that their release could come "no sooner than two years after [Biden] retires from any public office," according to the library.

Biden left office more than two years ago on January 20, 2017, but the library now says an updated agreement with Biden was made to keep the archive closed until at least the end of the year.

"The Biden senatorial papers are indeed still closed, pending completion of processing (still underway) and as per our agreement with the donor, which is that the papers would remain closed until the later date of 12/31/2019 or two years after the donor retires [from] public service," L. Rebecca Johnson Melvin, the head of the library's archives department, told the Huffington Post, adding that she also wouldn't guarantee the archive would open to the public immediately once the Biden-imposed deadline had passed.

Johnson Melvin did not initially respond to additional questions on whether other stipulations were made regarding specific documents or categories of documents.

In a Thursday morning email, she said there were "no other stipulations on release of the papers made by the donor."

The library is in possession of over 1,850 boxes of records as well as "extensive electronic records." The materials have been in the library's possession since June 11, 2012.

Biden graduated from the University of Delaware in 1965 and was given an honorary degree from the school in 2004. Last December, the university launched the Joseph R. Biden, Jr. School of Public Policy and Administration.

"By naming our school the Biden School, we not only recognize and honor our most esteemed alum in public service, but we also reinforce our commitment to elevating our school’s academic excellence and stature to be among the very best public policy programs in the nation," said university president Dennis Assanis. "We believe in the power of engaged citizenship, and we are inspired by Joe Biden’s lifelong commitment to honorable public service."

Biden will announce his presidential candidacy in a video on Thursday. Voting will begin in Iowa next February, just more than a month after the December 31, 2019, deadline imposed by Biden.

Update 10:20 a.m.: This post has been updated with comment from Melvin.