His Highness the Amir Sheikh Tamim bin Hamad al-Thani will patronise Tuesday morning the opening ceremony of the 6th Summit of the Gas Exporting Countries Forum (GECF), which will be held under the title "Natural Gas: Shaping the Energy Future", with the participation of a number of heads of states and governments, delegations of sisterly and friendly countries, high-ranking officials and experts in the field of energy, at Sheraton Grand Doha Resort and Convention Hotel.