The Pentagon has reportedly cancelled plans to deploy some 4,000 U.S. troops to Poland, a move that comes amid the United States’ review of its military presence in Europe.

The decision to cancel the deployment has been confirmed to several international outlets by unnamed U.S and NATO officials. The U.S. troops, reportedly between 4,000 and 4,200 belong to the 1st Cavalry Division’s 2nd Armored Brigade Combat team based in Ft. Hood, Texas.

According to reports, some of the troops and their military equipment was already in transit by the time their deployment was cancelled. The troops were slated to replace another unit from the same division that had been deployed to Poland last year.

An unnamed senior NATO military official confirmed the United States’ decision to Euronews on Thursday and claimed that the cancelled troops deployment “do not factor into NATO’s deterrence and defense plans.” Per the outlet, the Polish government was informed of the decision on Wednesday.

“NATO will continue to maintain a strong presence on its Eastern Flank,” the NATO official claimed to Euronews.

While no official announcement has been made by the U.S. at press time, outlets such as Reuters, Bloomberg, and the Army Times report having confirmed the cancelation of the troops’ deployment to Poland, citing unnamed sources.

Deputy Prime Minister and Defense Minister of Poland Władysław Kosiniak-Kamysz affirmed through social media that the issue “does not concern Poland” and that it relates to a previously-announced change in U.S. military presence in Europe.

“The rapidly developing capabilities of the Polish Armed Forces and the presence of U.S. forces in Poland strengthen NATO’s eastern flank,” Kosiniak-Kamysz wrote.

Acting Pentagon press secretary Joel Valdez told Politico that the decision to withdraw troops follows a “comprehensive, multilayered process that incorporates perspectives from key leaders in [U.S. military in Europe] and across the chain of command.”

“This was not an unexpected, last minute decision, Valdez emphasized.

The move comes days after the Pentagon announced that it will withdraw and relocate 5,000 troops from military bases in Germany over the next year. President Donald Trump has expressed the possibility of relocating additional troops in Germany beyond the announced 5,000. The majority of U.S. troops stationed in Europe are presently located in Germany, at approximately 36,000.

President Trump has also recently expressed the possibility of also withdrawing troops from other European countries such as Spain and Italy over their response to the war in Iran and the United States’ military actions against the rogue Islamic regime.

Speaking with The Telegraph on Thursday, former NATO Deputy Supreme Allied Commander Europe, General Sir Richard Shirreff, reacted to the announcement by urging the United Kingdom to “wake up to the fact” that the U.S. is no longer “underwriting European security.

“Bloody well wake up and smell the coffee Europe,” Gen. Shirreff said. “Wake up NATO to the fact America is no longer underwriting security. Wake up to the fact Europe and Canada have to revamp NATO to be an alliance of middle powers.”