The British government and the rest of the world "must do more" to rout extremism, Prime Minister David Cameron said in a 1,000-word statement published Sunday in The Telegraph. The declaration follows the latest update on last week's terrorist attack in Sousse, Tunisia, where now more than 30 Britons are counted among the 39 dead.

“We must be more intolerant of intolerance -- rejecting anyone whose views condone the Islamist extremist narrative and create the conditions for it to flourish,” Cameron wrote. “We must strengthen our institutions that put our values into practice.”

Cameron detailed his government's work with the United Nations, the European Union and the United States to form a government of national accord in Libya. British aircraft also have taken on the second highest number of airstrikes in Iraq, Cameron noted. Earlier this month, Cameron announced more than 100 British troops would be deployed to Iraq, the Telegraph reported.

Cameron said the British government and the rest of the world “must do more to work together and build our capacity to deal with terrorism.” In part, that effort includes preventing people from joining the Islamic State group, also known as ISIS or ISIL. “To defeat this poisonous ideology, we must be clear about why it is so wrong. We must expose and defeat what it is that persuades young people, from Tunisia to Kuwait, from Belgium to Britain, to join ISIL,” Cameron wrote.

Social media has been identified as one of ISIL’s primary recruitment avenues, Cameron noted. Indeed, the New York Times released a feature story Saturday detailing ISIS’s attempts at recruiting a 23-year-old American woman, who conversed with members of the Islamic State group on microblogging site Twitter as she converted from Christianity to Islam.

The attack at the Imperial Marhaba hotel in Sousse Friday was one of a series of terrorist attacks worldwide. “The man who did this, the smiling gunman with a Kalashnikov hidden in a parasol, demonstrates the level of evil we are dealing with,” Cameron wrote and referenced killings on Mount Sinjar in Iraq, at shopping malls in Kenya, inside magazine offices in Paris and within schools in Pakistan.

To address the Tunisia attack, the British government has sent more than 50 staff members, including police officers, experts and Red Cross relief members, to help in Sousse. Military medical liaison officers also have been deployed. The U.K. is working with Tunisian authorities to return the victims home.