Lewis Hamilton (afby71/Bigstock.com)

Formula 1 World Champion Lewis Hamilton has decided to keep #44 sticker on his Mercedes for this year's championship, despite earning the right to use #1.

New rules introduced last season stipulate that drivers must use the same number each season to help give drivers a more distinct identity. However, the reigning champion is permitted to use #1 if he wishes.

But Hamilton says #1 is "irrelevant".

"Everyone can get #1 when they win the championship, but it's irrelevant for me," explained the world no. 1.

"#44 means more to me than #1. It doesn't mean I'm not number one. #44 is my family number, it's the number I had when I first started racing; I won my first championship with #44. It means something to me.

"The #1 itself, Vettel's had it, Schumacher's had it, all of the champions have had it, but no one's had #44."

Having won the previous championship with Red Bull, Sebastian Vettel seized the chance to use #1. This year, however, he has resumed use of #5, having finished fifth in 2014.

F1 teams have been carrying out pre-season testing in Barcelona, affording the engineers time to iron out any teething problems.

Hamilton attained the best time in the Catalonian capital on Saturday, with 1m 23.022s (76 laps). Felipe Massa was second fastest in his Williams, (1m 23.262s, 102 laps), while Kimi Raikkonen was third quickest in his Ferrari (1m 25.276s, 136 laps).

Both Hamilton and constructor Mercedes will be hoping to repeat their successes in the 2015 season.

Those among our annual breakdown cover customers keen to catch the F1 action can do so on 15 March when the Australian Grand Prix takes place, broadcast live on Sky Sports. The BBC will be showing 10 races this year, with Sky broadcasting the remainder.