Showbiz
The Little Britain star is due to tie the knot with lover Kevin McGee, who he has been with for four years, this weekend.
Speaking after The British Comedy Awards, at which their show won the Best Stage Comedy title, the pair said Lucas had already decided on two friends to take the role.
Walliams commented: "Matt's got two best men - but I'm not one."
Lucas chipped in: "But David will be there. We have known each other since 1990 but the best men are people I've known for even longer.
"Also it's hard work, and I know how busy David is," he continued. "I thought I could give him a day off."
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