According to US entertainment website TMZ, the ceremony will be followed by a wedding banquet at New York's Plaza Hotel, which will feature ginger prawns, goat’s cheese truffles, braised beef short ribs, wild mushrooms and lobster with corn and mango relish.
An open bar will also be available for guests, as well as a wedding cake by famous New York designer Sylvia Weinstock.
The former Cheers star recently finalised his divorce from ex-wife Camille, so that he could marry Walsh, a former air hostess, as soon as possible.