UK woman, man found dead in Sydney

A murder-suicide could be the reason behind the deaths of a man and a woman in Sydney's inner west, police say.

Police discovered the bodies of the woman, a British national in her 20s, and a man in his 30s at a Newtown unit on Friday afternoon after concerns were raised for the pair's welfare.

A strikeforce was established to investigate the circumstances of their deaths with a murder-suicide a line of inquiry being investigated, a NSW Police spokeswoman told AAP on Sunday.

The UK Foreign and Commonwealth Office confirmed it was providing support to the family of a British national who died in NSW.

"Our staff are in contact with the New South Wales police," the FCO spokesman told AAP in a statement on Sunday.

© AAP 2018