DOHA,  (Reuters) – Roger Federer was proud to regain  his world number one status last year and wants to stay top of  the rankings for as long as he can, he said on Monday.

The 28-year-old Swiss leapfrogged Spain’s Rafael Nadal at  the top of the rankings thanks to his 2009 victories at  Wimbledon, the French Open and the Cincinnati Masters.

“I would like to stay the top player in the world …  because going from number two to number one was hard work and  not an easy thing to do especially with Rafa playing so well,”  Federer told reporters ahead of his Qatar Open title challenge.

“That was a major accomplishment for me and I would like to  stay there as long as possible and try to finish 2010 as world  number one.” The 15-times grand slam champion believes he can achieve  even better results than he did last year.

“I think I can definitely, if my body allows me, win many  more tournaments than I did in 2009,” said Federer ahead of  today’s first-round meeting with Belgian Christophe Rochus. “I  really just had to focus on the major events last year.