Saudi Arabia has formed a 34-state Islamic military coalition to fight terrorism, with a notable absence of Iran on the list.
There will be a joint operations centre based in Saudi Arabia's capital, Riyadh to coordinate operations, SPA, the state news agency, said.
The alliance includes countries from Asia, African and the Arab world. Shi-ite Muslim Iran, Sunni Saudi Arabia's rival for influence in the Arab world, was excluded.
The announcement cited "a duty to protect the Islamic nation from the evils of all terrorist groups and organisations whatever their sect and name which wreak death and corruption on earth and aim to terrorize the innocent."
The United States, among others, have increased pressure for Gulf Arab states to engage further militarily the fight against ISIS.
Deputy crown prince and Defence Minister Mohammed bin Salman told reporters on Tuesday that the campaign would "coordinate" efforts to fight terrorism in Iraq, Syria, Libya, Egypt and Afghanistan, but offered few concrete indications of how military efforts might proceed.
"There will be international coordination with major powers and international organisations ... in terms of operations in Syria and Iraq. We can't undertake these operations without coordinating with legitimacy in this place and the international community," bin Salman said.
"This comes from the Islamic world's vigilance in fighting this disease [Islamic extremism] which has damaged the Islamic world," he added.
"Currently, every Muslim country is fighting terrorism individually... so co-ordinating efforts is very important."
Asked if the new alliance would focus just on Islamic State, bin Salman said it would confront not only that group but "any terrorist organisation that appears in front of us."
Alongside the 34 members of this coalition, the SPA have said that ten other "Islamic countries" had expressed support, including Indonesia, but that "out of keenness to achieve the coalition as soon as possible" the current 34 members have been announced.
The list of 34 members: Saudi Arabia, Bahrain, Bangladesh, Benin, Chad, Comoros, Cote d'Ivoire, Djibouti, Egypt, Gabon, Guinea, Jordan, Kuwait, Lebanon, Libya, Malaysia, Maldives, Mali, Morocco, Mauritania, Niger, Nigeria, Pakistan, the Palestinians, Qatar, Senegal, Sierra Leone, Somalia, Sudan, Togo, Tunisia, Turkey, United Arab Emirates and Yemen.
Additional reporting by Reuters.