US President Joe Biden has signed gay marriage legislation into law much to the delight of music legend Cindy Lauper.

The 69-year old was among a celebratory crowd of thousands who bundled up against the cold at the White House yesterday to watch, and in her case, sing, at the ceremony.

She was joined on stage by singer songwriter Sam Smith who is gay and US Vice President Kamala Harris who recalled officiating at a lesbian wedding in San Francisco.

The legislation also protects interracial marriage.