Residents have expressed their confusion after a large vessel which looks like a warship was spotted off the coast of the city. 

The ship, which many suggested could be a Royal Navy vessel, was seen by Kat Lecheminant-Pay off the coast in Brighton this morning. 

Kat saw the ship from her living room window and posted the image to Facebook. 

Some reflected on the decommissioned HMS Brighton which was sold to scrap in 1985. 

The Argus: The HMS BrightonThe HMS Brighton (Image: Royal Navy)

The former Royal Navy anti-submarine frigate used to travel along the coast near Brighton once a year. 

Others thought it might be HMS Tyne, a river-class offshore patrol vessel.

The Argus: The HMS TyneThe HMS Tyne (Image: Tim Green)

Data from Marine Traffic, a website which provides information about maritime traffic, identified the ship as an Italian vessel called Alliance. 

The Argus: The Italian ship called AllianceThe Italian ship called Alliance (Image: Alan Jamieson)

The Alliance is a research vessel owned by Nato and operated by the Marina Militare, the Italian navy.