Garfield won't like this one bit.

Already facing the wrath of the entire civilised world, the Islamic State (ISIS) appears to have declared war on a new enemy — cats!

In a newly issued decree or fatwa, the terrorist group based in the occupied Iraqi city of Mosul warned all city residents against breeding cats inside their houses, Iraqi's Al Sumaria reported on Tuesday.

The news source did not spell out why ISIS has issued a ban on cats, saying only that the decree, along with other fatwas, "matches" jihadist "vision, ideology and beliefs."

Following the issuance of the decree, ISIS fighters began searching residences for cats.

The decree was considered a big surprise and a major turnaround, with observers noting that ISIS propaganda materials on social media had previously used photos of kittens to attract young recruits from various countries. In some of the photos, the cats are seen surrounded by guns and grenades or cuddled by ISIS fighters, according to RT.

A 2014 UN report took note of the significance of ISIS recruitment propaganda, stating that as many as 15,000 fighters from at least 80 countries had joined ISIS ranks. ISIS is fully aware of the "the terror and recruitment value of multi-channel, multi-language social and other media messaging," the report said.

Cats are not the only animals that the terrorist group have taken a stand against. In June, the ISIS issued a fatwa banning the breeding of pigeons, The Daily Mail reported.

The fatwa claimed that "the sight of the birds' genitals as they fly overhead is offensive to Islam."

The ISIS leaders' new abhorrence for cats is shared by fellow Sunni Muslims in Saudi Arabia.

In May, a Saudi cleric issue a fatwa prohibiting the taking of photos of the furry felines—and most anything else in the ultraconservative kingdom, according to RT.

Saleh bin Fawzan al-Fawzan, a member of the powerful Saudi Council of Senior Scholars, declared that "taking pictures with cats has been spreading among people who like to be like the Westerners."

Asked to clarify his decree, Fawzan said, "Taking pictures is prohibited if not for a necessity."

When someone asked if only cat pictures are prohibited, Fawzan snapped, "Not with cats, not with dogs, not with wolves, not with anything!"