U.S. President Barack Obama has topped the league of world leaders with 17 million followers on Twitter, according to a survey of the social networking usage by heads of government.
According to The Scotsman, the survey by U.S.-based PR firm Burson-Marsteller looking at the rise of "Twiplomacy", Obama was the first major politician to fully harness social media, in his 2007 campaign.
His Twitter account @BarackObama sent the most popular tweet of any world leader on 9 May.
The account is ranked fifth in the Twitterverse for followers, just behind @britneyspears, according to the study.
Venezuelan president Hugo Chavez - @chavezcandanga, is the second most popular leader on Twitter, and 38 per cent of his tweets are replies.
Among world leaders on Twitter, David Cameron came fifth with more than two million followers.
However, while Obama was top in terms of number of followers, only 1 percent of tweets from his account are replies, putting him well down the rankings in terms of engaging with his followers.
This compares with Rwandan president @PaulKagame, who has just under 71,000 followers, but whose tweets are more than 90 percent replies.
Like many government accounts, his team sent the vast majority of Obama's messages.
Only eight of the almost 5,000 tweets sent from the @BarackObama account were personally signed off with his initials "-BO," including a Valentine's Day message to his wife.
The study also found that politicians frequently discover Twitter during election campaigns, but once elected the accounts fall silent.