Yahoo Inc. has signed an agreement with T-Mobile to deliver oneSearch to 11 of the wireless carrier's European markets, thus intensifying the land-grab to become the premier mobile search provider.

The Internet giant has built a steady stream of oneSearch partnerships over the last year, with one struck with AT&T Inc. most recently. In all these partnerships, Yahoo becomes the exclusive mobile search provider on the carrier's deck, letting users find answers to search queries on their mobile devices.

"It's a partnership where oneSearch becomes the exclusive search provider for the carriers' phones and this illustrates our commitment to our mobile search philosophy, aggressive product development and worldwide distribution efforts," said Nicole Leverich, a spokeswoman for Yahoo.

"It is clear that Yahoo has emerged as the clear leader in mobile search," she claimed.

It is also clear that Yahoo is working hard to outdo Google in the mobile space. Google is the market leader in Internet search advertising and with DoubleClick, the No. 1 in online display ads.

Since introducing oneSearch, Yahoo has announced partnership agreements with 29 leading carriers worldwide, serving more than 600 million mobile subscribers.

"We have built a compelling oneSearch," Ms. Leverich said. "When you go into T-Mobile's Web and Walk portal, the search box is Yahoo's oneSearch. We have a similar agreement with AT&T, which should go live in the second quarter of this year."

Separately, Yahoo demoed its oneConnect technology at the Mobile World Congress show in Barcelona, Spain.

OneConnect is a mobile communications service that will combine integrated mobile messaging with a socially-connected address book. OneConnect is expected to become available in the Yahoo Go 3.0 and Yahoo's new mobile home page in the second quarter.

"We intend to reinvent mobile communications through Yahoo oneConnect," Ms. Leverich said.

Yahoo oneConnect is a mobile product with an open architecture that aggregates communications tools such as email, instant messaging, text messaging and social networks. It creates one starting point for all your favorite mobile Web destinations.

Yahoo oneConnect is designed to include features such as a socially-connected address book, which provide users the capability to integrate activity from popular social networks, professional networks and communities into their address book.

The new service will also include integrated mobile messaging and any messaging service will be able to use Yahoo oneConnect's open APIs to plug into the application's messaging feature, enabling consumers to access a wide range of popular services, such as Yahoo Messenger, Google Talk, AIM and MSN Messenger.

After its release, Yahoo oneConnect is expected to become available across hundreds of devices and mobile browsers around the world.

"OneConnect is the first mobile product that has an open architecture and aggregates communication," Ms. Leverich claimed. "It is a tool that creates one starting point for any services they are a using."