SAN FRANCISCO--Twitter has concluded the hunt for its first PR agency by hiring Edelman, the Holmes Report can reveal.

The social media giant is understood to have appointed Edelman to handle a short-term project, focused on some specific upcoming consumer launches. Edelman is believed to have prevailed following a pitch that included three other firms.

A source familiar with the situation told the Holmes Report that  Twitter will reassess its PR requirements after Edelman’s brief is complete.

Edelman’s projects will be consumer-focused, and are not expected to consider Twitter’s corporate and public affairs needs. One of the three launches is Twitter’s integration into Apple’s upcoming iOS5 operating system, while the other two have yet to be announced.

According to AdAge, which broke news of the pitch last month, the five-year-old company is likely looking to “communicate more aggressively and fight for consumers time”, amid increasing competition from Google and Facebook.

Twitter yesterday confirmed that it has 100 million ‘active users’, who log in at least once month. Around 50 percent of these users log in every day.

The PR review followed the arrival of Sean Garrett last year as Twitter’s VP of communications. In addition, Pam Kramer joined earlier this year Twitter’s VP of consumer marketing.

Neither Garrett nor Kramer responded to request for comment. Edelman US president/CEO Matt Harrington declined to comment.

Twitter has grown its strength considerably over the past year, from 250 to 600 employees, in the process beefing up its PR, public affairs and marketing teams.