HOUSTON (Reuters) -The arbitrators in a legal dispute between Exxon Mobil ( XOM ) and Hess have reached a decision related to a major oilfield project in Guyana, according to two sources familiar with the matter, with the ruling determining whether Chevron ( CVX ) can move forward with its planned acquisition of Hess.

The Paris-based International Chamber of Commerce, which is overseeing the arbitration case, is now reviewing the decision before it is released to the parties.

It is unclear what the arbitrators decided or when the decision will be released. 

Exxon, Hess, Chevron ( CVX ) and the ICC did not immediately respond to requests for comment.