US Defence Secretary Chuck Hagel will step down from his post after coming under pressure from President Barack Obama, The New York Times reported .

The president is expected to announce Hagel’s resignation in a Rose Garden appearance Monday, the daily said, adding that the removal of Hagel – the sole Republican on his national security team – is the first cabinet-level casualty of the collapse of Obama’s Democratic majority in the Senate.

The decision was taken last Friday after a series of meetings over the past two weeks, the prestigious daily quoted senior administration officials as saying.

The officials said that Obama’s decision to remove Hagel, 68, was due to a recognition that the threat from the Sunni radical group Islamic State would require a different kind of skills than those that Hagel has brought on to employ, the report said.

Hagel, 68, is expected to meet with President Obama at the White House at 11 a.m.

Hagel, a Republican, is the first member of Obama’s team to step down following the sweeping midterm elections where Republicans took control over the Senate.

Hagel took office Feb.27, 2013.

A senior defense official said that Hagel submitted his resignation letter to Obama Monday morning and that the president accepted it. Hagel agreed to remain in office until his successor is confirmed by the Senate, the official said.

The official said both Hagel and Obama “determined that it was time for new leadership in the Pentagon,” adding that they had been discussing the matter over a period of several weeks.

The president is not expected to nominate a new Pentagon chief Monday, according to one official.

The officials insisted on anonymity because they were not authorized to discuss the matter by name ahead of Obama’s official announcement.

Hagel is a Republican who served as senator from Nebraska and became a critic of U.S. involvement in Iraq. Obama nominated him to succeed Leon Panetta as Defense Secretary in his second term.

Hagel served in the Vietnam War and received two Purple Hearts.

Recent questions about Hagel’s future at the Pentagon were prompted in part by his decision to postpone a long-planned trip this month to Vietnam. At the time, officials said he needed to remain in Washington for congressional consultations, but that did not stop speculation that the White House might be looking for a replacement for the final two years of Obama’s term reported FOX NEWS.

Just last week Hagel was asked about the speculation during an interview on the Charlie Rose show. He was asked whether he’s concerned by the speculation