Joint venture partner Fastnet Oil & Gas announced the spud on Monday.
The planned target depth of the well is 4000 metres in water depths of about 600 metres.
Fastnet said the well is expected to take three months to reach target depth to test multiple objectives.
According to Kosmos, the well is expected to hold 360 million barrels of oil equivalent of prospective mean resources in the Lower Cretaceous objective.
Fastnet is carried through drilling costs to a maximum of $100 million following the farm-in
