Yahoo Inc's board will meet on Sunday to vote on whether to offer $1.1 billion in cash for New York-based blogging service Tumblr, tech blog AllThingsD cited sources close to the situation as saying.

Yahoo! may be on the verge of closing its biggest acquisition during the 10-month reign of chief executive Marissa Mayer as she tries to attract more traffic and advertisers to the Internet company's website and mobile applications.

If Yahoo! board signs off, the deal could be announced tomorrow. In an invitation sent earlier, Yahoo! promised to unveil "something special" tomorrow evening in New York.

The event is being held in a Times Square lounge located about three kilometres from Tumblr's headquarters.

Yahoo! has only said that Mayer will be on hand to unveil something related to a product.

Buying Tumblr would fulfil Mayer's goal of reaching a wider audience on smartphones and tablet computers.

Tumblr serves up a constantly changing collage of stories, photos and other digital content served up by users who are increasingly connecting to the service through its mobile applications. The service is also one of the hottest sites among teens and young adults.-Reuters