President Trump announced Wednesday morning the military will no longer allow transgender individuals to serve in "any capacity" in the military.

"After consultation with my Generals and military experts, please be advised that the United States Government will not accept or allow Transgender individuals to serve in any capacity in the U.S. Military. Our military must be focused on decisive and overwhelming victory and cannot be burdened with the tremendous medical costs and disruption that transgender in the military would entail. Thank you," Trump said in a series of tweets that remained unfinished Wednesday morning.

A Pentagon spokesman said to contact the White House for further information.

"We refer all questions about the President's statements to the White House," Navy Capt. Jeff Davis said. "We will continue to work closely with the White House to address the new guidance provided by the Commander-in-Chief on transgender individuals serving the military. We will provide revised guidance to the Department in the near future."

Asked about rumors that the Pentagon was blindsided about the announcement, one public affairs official told the Washington Examiner, "I think the reports are pretty accurate that no one knew. I certainly had no idea."

Mattis is on vacation and was spotted in his home state of Washington. His chief spokesperson Dana White is also on leave.

No one at the Pentagon could say if Mattis had been informed beforehand of the president's decision. Sources on the House and Senate Armed Services Committees said they were not notified ahead of the decision.

Last year, then-Defense Secretary Ash Carter announced that transgender people already in the military could serve openly, and directed service chiefs to come up with a policy to allow transgender recruitment by July 1. Defense Secretary Jim Mattis announced a delay in the implementation on June 30.

"Our decision to delay the accessions of transgender individuals into the services was largely based on a disagreement on the science of how mental health care and hormone therapy for transgender individuals would help solve their medical issues that are associated with gender dysphoria," the Gen. Paul Selva, vice chairment of the Joint Chiefs, said on July 18.

In a report last year, the Rand Corp. estimated that about 2,450 transgender people serve in the active component of the military, with another 1,510 in the reserve.

"Only a subset will seek gender transition–related treatment. Estimates derived from survey data and private health insurance claims data indicate that, each year, between 29 and 129 service members in the active component will seek transition-related care that could disrupt their ability to deploy," the report said.

Before Mattis decided to delay implementation of the new recruiting policy, more than a dozen Democrats sent him a letter urging him to move forward with the policy to allow transgender people to enlist.

"We strongly encourage you to deny the request of a six-month delay in transgender policy implementation," the members wrote in their letter. "Throughout our nation's history, the Department of Defense has benefited from diversity and equal opportunity programs and policies, which support recruitment, retention and promotion. There are thousands of transgender individuals in our military today. There should be no further delay in implementing this policy and allowing transgender individuals to serve the country they love."

— Jamie McIntyre and Travis J. Tritten contributed to this report.