WASHINGTON (AFP) - US President Barack Obama expressed pride on Tuesday after basketball center Jason Collins came out as gay, calling it a measure of the growing acceptance of homosexuality in American society.

Obama told a White House news conference that he spoke with Collins on Monday after the NBA free agent became - via the pages of Sports Illustrated - the first active player in any major US professional sport to come out as gay.

"I told him I couldn't be prouder," Obama, who last year became the first serving president to declare his support for same-sex marriage, said at the tail end of a White House news conference.

"One of the extraordinary measures of progress that we've seen in this country has been the recognition that the LGBT community deserves full equality," he added.

"Not just partial equality, not just tolerance, but a recognition that they're fully part of the American family."

For young people "who are struggling" with being gay or lesbian, the president added, it is a "great thing" for Collins to have come forward as a fearless role model they can look up to.

"This is just one more step in this ongoing recognition that we treat everybody fairly, that everybody's part of a family and that we judge people on the basis of their character and performance, and not their sexual orientation," he said.

"I'm very proud of him, alright."

Earlier in the day, Collins, formerly with the Washington Wizards, said in an interview he has never been happier after his ground-breaking announcement, and he hoped other gay athletes will now come out, too.