British Prime Minister David Cameron adopted the term "Daesh" to refer to the Islamic State group on Wednesday and urged others to follow suit to avoid lending the militants credibility.
Cameron had previously used "ISIL" to refer to the extremist group, which is also known as "ISIS", before switching to Daesh, which has negative connotations and is based on an Arabic acronym.
"Daesh is clearly an improvement and I think it's important that we all try to use this language," Cameron told parliament during a debate on whether Britain should join air strikes against the group in Syria.
"Frankly this evil death cult is neither a true representation of Islam nor is it a state," Cameron said, branding its members "women-raping, Muslim-murdering, mediaeval monsters".
A government Twitter account that had been called "UK Against ISIL" was changed to "UK Against Daesh" as Cameron made the announcement.
"#Daesh is Arabic acronym for #ISIL.Daesh hates the term + sounds similar to Arabic words Daes & Dahes: 'to trample' & 'one who sows discord'," read a tweet on the account.
News organisations and international governments have been divided over what to call the group, with French President Francois Hollande referring to it as "Daesh" and the United States President Barack Obama calling it "ISIL".
ISIL stands for the Islamic State of Iraq and the Levant, while ISIS is the abbreviation for the Islamic State of Iraq and Syria.