BASEL, Switzerland - Roger Federer will miss Switzerland's Davis Cup series against the United States and next week's tournament in Dubai as he recovers from a back injury.

Federer said on his website Tuesday he did not have enough time to completely strengthen his back after hurting it last fall. He says he is taking a precautionary measure.

"After my back injury last autumn I didn't have enough time to build up the affected muscles again and fully heal," Federer said. "I will use the coming weeks for further rehabilitation in order to be sure that I'm fully fit for the rest of the season."

Switzerland faces the United States in the first round of the Davis Cup on March 6-8 in Birmingham, Alabama.

"I'm sorry to tell you that I won't be taking part in either the Dubai tournament or the Davis Cup encounter in the USA," Federer said. "This decision was very difficult for me, because I won't just be missing one of my favourite tournaments of the tour, but also the chance to go through to the next round with my teammates."

Federer, who is ranked No. 2 and has won 13 Grand Slam titles, lost to Rafael Nadal in five sets at the Australian Open final.

Omg, This sucks so much!!!