HELSINKI - Global sales of mobile phones shrank 2 per cent in the first quarter due to slower demand in the Asia-Pacific region, the first year-on-year fall since 2009, research firm Gartner said on Wednesday.

"The first quarter, traditionally the strongest quarter for Asia ... saw a lack of new product launches from leading manufacturers, and users delayed upgrades in the hope of better smartphone deals arriving later in the year," analyst Anshul Gupta said in a statement.

Gartner said the slow start to the year made it cautious about the rest of 2012, and will lower its full-year cellphone market outlook by some 20 million handsets.