US President Donald Trump has signed an executive order that prevents transgender women from competing in female categories of sports.

The order provides guidance, regulations and legal interpretations, and it will enlist the Department of Education to investigate high schools thought to be non-compliant.

Republicans say it restores fairness to sports but LGBT advocacy and human rights organisations have described the move as discriminatory.

The order, which goes into effect immediately, largely covers high schools, universities and grassroots sports.

A number of sporting governing bodies, including swimming, athletics and golf, have banned transgender women from competing in the female category at elite level if they have gone through male puberty.

According to White House officials who briefed reporters on Wednesday morning, this latest order empowers the Department of Education to investigate how schools implement Title IX, a US law that bans sex discrimination in federally funded education programmes.

An administration official said that the executive order will reverse the position of the Biden administration which in April last year said that LGBT students would be protected by federal law, although it did not give specific guidance on transgender athletes.

"If you let men take over women's sports teams or invade your locker rooms, you will be investigated for violations of Title IX and risk your federal funding," Trump explained.

Additionally, the White House plans to bring in sporting bodies - such as the National Collegiate Athletics Association, or NCAA - to come to the White House to meet female athletes and their parents to discuss concerns.

The official who discussed the order, said the US would do all it could to prevent transgender athletes from competing against females in International Olympic Committee competitions that take place on US soil.

President Trump specified that the order would include the 2028 Olympic Games in Los Angeles.

He has said he will deny visas for transgender Olympic athletes trying to visit the US to compete at the LA Games.

Ahead of signing the executive order, Trump declared that "the war on women's sports is over", saying that during the LA Games, "my administration will not stand by and watch men beat and batter female athletes."

He said he would direct the secretary of homeland security "to deny any and all visa applications made by men attempting to fraudulently enter the United States while identifying themselves as women athletes..."

IOC has been approached for comment.

White House officials described the policies as being broadly popular with Americans, and critical to ensuring "fairness" for women in sports, as well as safety.

In a statement, Human Rights Campaign President Kelley Robinson said that the order "exposes young people to harassment and discrimination, emboldening people to question the gender of kids who don't fit a narrow view of how they're supposed to dress or look".

"For so many students, sports are about finding somewhere to belong," Ms Robinson added. "Not partisan policies that make life harder for them."

Less than 1% of the population over the age of 13 in the US are transgender, according to a study by the UCLA Williams Institute, and the number playing sports is smaller.

On Trump's first day in office on 20 January, he signed a separate order calling for the federal government to officially define sex as either being male or female.