Last month the share price dropped after it became clear a maritime border dispute between Ghana and Ivory Coast could delay Tullow's multi-billion dollar Tweneboa, Enyenra and Ntomme (TEN) oil project.

But The Hamburg-based International Tribunal for the Law of the Sea (ITLOS) ruled on Saturday the project could continue on the condition that Ghana does not start any new drilling in the area.

Tullow's shares rallied on the news after the London stock market opened on Monday, rising up to 456.9 pence, the highest level since late November and up more than 8 percent on the previous session. The shares were trading up 2 percent at 427 pence at 0816 GMT.

The tribunal is expected to give a final ruling on the case in 2017, months after the TEN oil project is expected to start production.

Tullow said it had already drilled all of the 10 wells expected to be operational when the field starts pumping oil.

"Tullow is not a party to this arbitration process and will now await a decision by the Government of Ghana on how it will implement the provisional measures order," the company said in a statement.

Analysts at Stifel said even if Ghana should lose the case in 2017 Tullow could expect financial compensation.

(Reporting by Karolin Schaps; editing by Jason Neely, Greg Mahlich)