The IUMS issued a statement on Sunday calling on people of all faiths, especially Muslims, to join the strike and demand a cease-fire.
The statement also criticized the UN Security Council for failing to stop the war and suggested a reform of its veto system.
The IUMS Secretary-General, Ali Al-Qaradaghi, said that the strike was a way of showing solidarity with the Palestinians and urging the international community to act to end the violence.
He urged Muslims to invite others to participate in the strike and to spread the message of peace and justice.
The strike comes as Israel continues its bombardment of Gaza, which it resumed on Dec. 1 after a brief humanitarian pause.
The Israeli offensive, which began on Oct. 7 in response to a cross-border attack by Hamas, has killed nearly 18,000 Palestinians, mostly civilians and children, and injured more than 49,000 others.
The Israeli casualties in the Hamas attack were 1,200, according to official figures.
