By Reuters Staff Slideshow ( 2 images ) PARIS (Reuters) - Aircraft leasing giant AerCap’s acquisition of rival GECAS will reduce competition in the aircraft market, the head of global airline industry body IATA warned on Wednesday. “We understand that the situation of the leasing companies is difficult,” IATA Director General Alexandre de Juniac told Reuters. “But combining the two to have a big player (in) a very dominant situation is not good news for us.” The world’s two largest aircraft lessors announced plans last week to combine, with Ireland’s AerCap agreeing to pay more than $30 billion for GECAS, the air finance business of General Electric.