Breaking: Sharks circle after whale carcass washes up on Perth beach

The whale carcass has drawn a small crowd of onlookers at City Beach. (ABC News: Lucy Murray)

A whale carcass has washed up on Perth's City Beach, with authorities issuing multiple shark warnings for the popular swimming spot.

Several sharks have already been spotted circling in the area.

Local surf lifesavers found the carcass this morning and sounded the alarm.

Authorities are yet to confirm what species the whale is. (ABC News: Lucy Murray)

"It is possible the carcass will continue to act as an attractant that could lead to sharks coming in close to shore along this stretch of coast," the Department of Primary Industries and Regional Development (DPIRD) warned.

The SharkSmart website has since issued several alerts for sharks seen at City Beach.

The website said two white sharks, one measuring 5 metres and another 4 metres, were seen 10 metres offshore at City Beach, about one hour after the carcass was spotted.

A 3.5-metre unknown species of shark was also reported by the Surf Life Saving helicopter, and a 2.5-metre shark of unknown species was seen circling 10 metres offshore.

DPIRD said people should exercise additional caution and follow any beach closures.

The department did not know the size of the whale carcass or the species.

The Town of Cambridge, which is managing the carcass, has been contacted for comment.

The warnings come just 10 days after a fatal shark attack at Sorrento beach, about 15 kilometres further north.

Swimmer Greg O'Neill was swimming close to the shore when he was attacked by a large great white, prompting Fisheries Minister Jackie Jarvis to issue a catch-and-kill order for the animal.