TAORMINA, Italy, May 26 (Xinhua) -- The leaders of the Group of Seven (G7) industrialized nations on Friday signed a joint declaration on combating terrorism.

The 15-point document says the fight against "violent extremism" is "a major priority" of the G7, which "will bring the fight ... to a higher level by relentlessly preventing, investigating and prosecuting terrorist acts, their perpetrators and supporters".

The leaders pledged to "combat the misuse of the Internet by terrorists" to work together to manage "the risk posed by foreign fighters as they disperse from theatres of conflict" and to "take action to cut off sources and channels of terrorist financing".

Among the measure is "expansion of the use of Passenger Name Record (PNR) and Advance Passenger Information (API) in traveler screening", according to the declaration.

"Since the lack of social and economic inclusiveness and opportunities may contribute to the rise of terrorism and violent extremism, we commit to address these issues through a comprehensive approach linking together security, social inclusion, and development," the declaration said.

"(This declaration) is also a strong message of solidarity to the UK after what happened in Manchester," Italian Prime Minister Gentiloni said as the document was passed around the table, where each of the leaders signed it in turn.

Terrorism was pushed to the top of the G7 summit agenda after a suicide bomber claimed 22 lives and wounded dozens others when he blew himself up at a concert by American singer, Ariana Grande, in the British city of Manchester on Monday.

"With this declaration we showed our unity, our commitment, our determination to continue and strengthen our fight against terrorism," Gentiloni said, adding it is "a message of friendship and community with the UK".

British Prime Minister Theresa May responded: "Thank you for your support after this horrific attack."

The joint declaration "shows our fierce determination to use every tool available to us to fight terrorism and protect our people", May added.

The ongoing 43rd summit of G7 leaders in the Sicilian town of Taormina includes the heads of state of Britain, Canada, France, Germany, Italy, Japan, and the United States, plus the EU.