(6B) 2[ where in the case of a non- resident (not being a company) or of a foreign company deriving income (not being salary, royalty or fees for technical services) from Government or an Indian concern in pursuance of an agreement entered into by the Central Government with the Government of a foreign State or an international Organisation, the tax on such income is payable by Government or the Indian concern to the Central Government under the terms of that agreement or any other related agreement approved by the Central Government, the tax so paid;]