Managing-Director of the National Iranian Offshore Oil Company (NIOOC) Mahmoud Zirakchianzadeh said on Sunday that increasing the output from joint oilfields was one of the priorities of his company. He further voiced Iran\'s preparedness to to cooperate with Kuwait for the expansion of the Arash joint oilfield. The massive Arash field\'s reserves are believed to contain around 20 trillion cubic feet (tcf) of natural gas. The field is shared by Iran, Kuwait, and Saudi Arabia where it is known as \'Dorra\' and is a contested area between Tehran and Kuwait. Kuwait claims it owns more than 50 percent of the field, while Iran believes that the two countries have equal shares. Zirakchianzadeh added that Iran had officially offered the positive diplomacy of cooperation instead of unitization to the Kuwaiti side. Earlier, Iranian Oil Minister Rostam Qassemi had underlined that the development of Iran\'s Joint Oil and Gas fields sets the main priority for his ministry. Speaking in a meeting with directors of the oil and gas companies active in the South Pars region, the oil minister said that development of joint oil and gas fields is the first priority of the oil ministry in both land and sea border regions Also in 2011, Tehran and Baghdad agreed to set up joint expert committees to finalize technical and financial details of a deal over developing joint oil fields. The two countries have 23 joint oil fields in their border regions.