Kanye West and punk icon Patti Smith have been added to U2's expanded Vertigo world tour.

The acts join the likes of Keane, Pearl Jam, Beck and John Mayer, who have already signed up to fill support slots on the Irish supergroup's US tour.

West will give U2 a tour ending to remember when he joins the group for its last four shows in December (05), while Smith will join them at New York City's Madison Square Garden in November (05).