Saudi Arabia has formed a coalition of 34 mainly Muslim countries - including powers such as Egypt and Turkey - to coordinate a fight against "terrorist organisations".
The alliance was announced by Mohammed bin Salman, the country's defence minister and deputy crown prince, on Tuesday.
Arab countries such as Qatar and the UAE will join the coalition, as well as Middle Eastern, Asian and African states including Pakistan, Malaysia, and Nigeria.
"It is time that the Islamic world take a stand, and they have done that by creating a coalition to push back and confront the terrorists and those who promote their violent ideologies," said Adel al-Jubeir, Saudi's foreign minister, speaking in Paris.
When asked if the alliance would deploy troops on the ground, Jubeir said "nothing is off the table".
Saudi Arabia's regional rival Iran and its allies, Syria and Iraq, were excluded from the alliance, despite the states sharing a common enemy in the Islamic State of Iraq and the Levant (ISIL) group.
Bin Salman said the states would work together to target "any terrorist organisation, not just ISIL" in countries including Iraq, Syria, Libya, Egypt, and Afghanistan.
Military operations would work in accordance with local laws and in cooperation with the international community, he added.
In an earlier press statement issued by the Saudi Press Agency, officials said the group would be led by Saudi Arabia, which would host a "joint operations centre to coordinate" efforts.
The United States welcomed the announcement of the anti-terrorism alliance.
"We look forward to learning more about what Saudi Arabia has in mind in terms of this coalition," Ashton Carter, US defence secretary, told journalists in Turkey.
"But in general, it appears it is very much in line with something we've been urging for quite some time, which is greater involvement in the campaign to combat ISIL by Sunni Arab countries."
Turkey said it was set to assist any time, anywhere.
"Turkey is ready to contribute by all its means to all gatherings that aim to fight terrorism, no matter where or by whom they are organised," Prime Minister Ahmet Davutoglu told reporters in Ankara.
Most of the countries in the coalition are currently involved in military operations against ISIL or have been targeted by the group.
Saudi Arabia and its Gulf allies have carried out air strikes against the fighters in Syria and were targeted by the group in Yemen, where they are involved in a separate war against Iran-backed Houthi rebels.
In August, an ISIL suicide bomber killed 15 people, mainly special forces soldiers, at a mosque in Asir province, bordering Yemen.
ISIL has also targeted Saudi Arabia's Shia minority, killing dozens in bomb attacks on mosques.
Saudi authorities have carried out raids detaining hundreds of suspected ISIL members and sympathisers in response.
| Saudi Arabia announces new Muslim 'anti-terrorism' coalition
Source: Al Jazeera