NICOSIA, June 30 (Reuters) - Exxon Mobil and Qatar Energy signed an agreement with Cyprus on Tuesday to declare two offshore gas fields commercially viable, marking a milestone in the eastern Mediterranean island's efforts to develop its offshore gas reserves.

The (declaration of commercial viability) signed in Nicosia is a step forward in a pivotal project for the region's ambitions to supply Europe with more gas.

• ExxonMobil announced discoveries in two offshore fields known as Glaucus and Pegasus.

• Cypriot officials have stated that the combined volume of the discoveries could range between eight and nine trillion cubic feet.

• Cypriot President Nicos Christodoulides, speaking in Nicosia alongside representatives from ExxonMobil and Qatar Energy, said the agreement signed on Tuesday "represents a major step towards establishing the Eastern Mediterranean as an alternative energy corridor for Europe."

• Officials added that some additional drilling will be required in the two offshore fields before moving to the initial engineering and design phase.

• John Ardell, vice president of ExxonMobil, said the final investment decision is expected around 2029, with production starting in 2033.

• Qatar Energy signed a preliminary agreement with ExxonMobil and the Egyptian government in May to study the development and marketing of gas discoveries in Cyprus using existing gas and liquefied natural gas infrastructure in Egypt.

• Ardell explained that the reserves from the Glaucus and Pegasus fields will most likely be transported via a pipeline connected to Egypt.

• Other discoveries in Cyprus are also being considered for linking to Egypt’s underutilized infrastructure, such as the Aphrodite field, whose reserves range between 3.5 and 4.5 trillion cubic feet and in which Chevron has obtained a license to operate, and the Kronos field, whose reserves exceed three trillion cubic feet and in which the Italian company Eni has obtained a license to operate in partnership with the French company Total.