Southeast Asia's biggest telecom operator, Singapore Telecommunications , said on Monday it would start to sell a social networking phone model INQ Mini 3G, targeting young customers.

The deal is a milestone for INQ Mobile, a unit of Hong Kong's Hutchison Whampoa <0013.HK>, who so far has sold its phones through Hutchison's operators in different countries.

One of the biggest operators has chosen us. This is confirmation that we are serious, INQ's Chief Executive Frank Meehan told Reuters.

INQ is benefiting from its early move to make reasonably priced phones for connecting to social networks and the Internet in general -- a move large handset makers like Nokia and Motorola are only now following.

Operators are not looking at only differentiating at the top-end, but now they look at many different price levels, Meehan said.

SingTel said it would unveil pricing details for the phone later in the week when the model goes on sale in Singapore. INQ has earlier said the model would cost operators less than $140, enabling many carriers to offer it for free with monthly contracts.

INQ Mini 3G is the first mass-market phone with an Internet-based Twitter client. The phone will use Internet connections for sending the 140-character messages, called Tweets, not text messages as in Twitter's own service.

Twitter has seen explosive growth this year.

The majority of visits to online social networks are still made by people sitting at a computer telling their friends where they are and how they are feeling, exchanging opinions on their favorite movies and music or up loading pictures.

INQ, however, has proved the spontaneous and personal nature of much of that communication also lends itself to the handset. The INQ1 model, dubbed the Facebook phone, won the award for best phone at the Mobile World Congress trade show in February.

INQ1 and new INQ models integrate key features of Facebook and other social networking sites into the phone's address book, removing the need to separately log on to the service.

Meehan said the company plans to enter the increasingly crowded smartphone market next year, introducing a phone to operate on Google's Android operating system.

For customers there hasn't really been anything in Android world to set them on fire, Meehan said. We think we can, and we have to, leapfrog quickly. Most other cellphone makers plan to also introduce Android phones, and Motorola unveiled last week its first cellphone to run on Android, but analysts questioned if it could revive the once-dominant handset maker's fortunes.

(Reporting by Tarmo Virki; Editing Bernard Orr)

Electronics Android Phone