President Joe Biden has issued an executive order that overturns a ban on transgender people serving in the U.S. military.

In 2016, then-President Barack Obama allowed transgender people to join the military and to receive medical treatment to transition to the gender with which they identity. Trump banned recruitment of transgender people but allowed those already in the military to continue serving.

"Today, I repealed the discriminatory ban on transgender people serving in the military. It's simple: America is safer when everyone qualified to serve can do so openly and with pride," Biden tweeted.

Trump had said allowing transgender people to serve would be disruptive and expensive.

"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," Trump tweeted in 2017, announcing the new policy.

Biden's defense secretary, retired Army General Lloyd Austin said he supports the new policy change.

"I fully support the President's direction that all transgender individuals who wish to serve in the United States military and can meet the appropriate standards shall be able to do so openly and free from discrimination," he said in a statement. "The Department will immediately take appropriate policy action to ensure individuals who identify as transgender are eligible to enter and serve in their self-identified gender."

The Washington-based Human Rights Campaign, which advocates for sexual minorities, tweeted, "A grateful nation salutes all who have served and hoped for this moment. ... If you fight for your country, you deserve a country that will fight for you."

There is no official data on the number of transgender people serving in the military and estimates vary widely. Gays and lesbians gained the right to serve openly in the U.S. military during former President Barak Obama's first term, when Congress repealed a law that subjected them to expulsion if their sexuality became known.