Cameron takes to twitter in Russia-UK diplomatic spat

British Prime Minister David Cameron
Getty Images

U.K. Prime Minister David Cameron took to social media Friday to defend his country after reports that Russia had mocked Britain as a small island of no significance.

A diplomatic spat arose at the G-20 meeting of major countries in St. Petersburg, when reports circulated that a Russian official had told reporters that Britain held no importance on the geopolitical stage.

This followed tense discussion about the deteriorating situation in Syria, a topic on which Cameron faced embarrassment last week when members of parliament voted against any military strike on the country.

Cameron launched an impassioned defense of Britain at a press conference on Friday, according to media reports, before reiterating his message on Facebook and Google Plus.

"Britain may be a small island, but I would challenge anyone to find a country with a prouder history, a bigger heart or greater resilience," Cameron tweeted.

(

He followed up with another message two minutes later. "We are very proud of everything we do as a small island—and I definitely can't fit it all in a tweet."

He took to Google Plus to express his feelings at length.

"Britain is an island that helped to abolish slavery, that has invented most of the things worth inventing, including every sport currently played around the world, that still today is responsible for art, literature and music that delights the entire world. …" Cameron wrote in a six-paragraph post.

He listed the country's achievements, which included the world's sixth-largest economy, the fourth-best-funded military, "one of the best records" for art and literature, and contribution to philosophy and global civilization. He also mentioned Britain's role in World War II in helping rid the world of the threat of fascism.

Cameron's message met with a mixed response on Twitter and Google Plus. While many followers praised his patriotism, others said the U.K. was shamed by its failure to commit to a strike on Syria.

Syed Anwaar ul Haq Shah said, "The role you are playing is not good at international level. ... The message Assad got from the international community is that he can kill people."

(Read more: Cameron's fracking backing gets warm welcome)

Other followers took a wider look at Britain's role on the geopolitical stage.

"Yes, we have a proud history, but we have an awful lot of history which we shouldn't be proud of. … Yes, we helped to abolish slavery, but we were largely responsible for creating the transatlantic slave trade in the first place," George Forth said.

PM Cameron sidelined on Syria

Cameron's tweets Friday were preceded by a blunter post by a politician from the prime minister's Conservative Party.

"[Russian President Vladimir] Putin really is a tosser," said Henry Smith, the member of parliament for Crawley, a district about 30 miles south of London. His post was retweeted by 597 people and favorited by 177.

Smith did not elaborate but appeared to backtrack slightly an hour later. "Huh, apparently I can't mention the word I used about Putin on the BBC World Service," he tweeted.

Since the failed vote on military action, Cameron and the U.K. government have sought to emphasize the importance of the country's humanitarian role in Syria. In a press release, the government highlighted the £400 million ($623 million) the nation has donated to ease the crisis and cited Justine Greening, the international development secretary, as saying the country had "led the way" in responding.

Putin's chief spokesperson, Dmitry Peskov, has reportedly denied he was responsible for the negative comments about the U.K., insisting they did not reflect Russia's "positive" relations with the country.

—By CNBC's Katy Barnato