Sir Ian McKellen has revealed he is to conduct the wedding of his friend Patrick Stewart and the actor's fiancee Sunny Ozell.

Sir Ian McKellen is "going to marry" Patrick Stewart.

The 73-year-old actor will officiate at the ceremony between his friend and 'X-Men' costar and his fiancee, jazz singer Sunny Ozell, when they tie the knot in Masachusetts.

He said: "I'm going to marry Patrick [Stewart]. I am going to officiate at his wedding.

"In Massachusetts, in the middle of America somewhere, you get a friend along, and I read out the words, and Sunny and Patrick will then be married."

The British actor revealed it won't be the first time he has officiated at such a service.

Speaking on an upcoming episode of 'The Jonathan Ross Show', he added: "I've done it once before with two guys having a civil partnership. I was crying my eyes out.

"I wore a white gown which I bought in India. You mustn't upstage the bride."

Massachusetts' Secretary of Commonwealth offers a service that allows a family friend or relative to perform a couple's wedding ceremony for a fee of $25.

Patrick, 72, and Sunny, 35, have been dating since 2009.