Twitter (TWTR) - Get Report will begin testing expanding the allotted length per tweet to 280 characters from 140 characters, the social media company wrote in a blog post on Tuesday.

The initial expansion will be rolled out to a "small group" of users who tweet in languages which make it difficult to fit messages into the allotted character limit.

"We understand since many of you have been Tweeting for years, there may be an emotional attachment to 140 characters - we felt it, too," Twitter product manager Aliza Rosen said. "But we tried this, saw the power of what it will do, and fell in love with this new, still brief, constraint."

Shares of Twitter closed lower on Tuesday but were rising nearly 2% in after-hours trading following the announcement.

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