UN Secretary-General Ban Ki- moon on Wednesday said that \"it is clearly unacceptable that Iraq\' s territory is being used\" for cross-border attacks against Turkey, urging Iraq and Turkey to \"find a peaceful solution to this challenge.\" The secretary-general, in a statement issued here by his spokesman, \"expresses his concern over the attacks in the Hakkari province of Turkey, reportedly by Kurdish elements operating from Iraqi territory, which have left many Turkish soldiers dead.\" The secretary-general made the statement in response to an attack by the Kurdish rebels in Turkey which killed at least 24 soldiers near the Turkish border with Iraq. The attacks by the separatist Kurdish Workers\' Party, known as the PKK, took place in eight locations in Cukurca and Yuksekova in Hakkari Province near Turkey\'s rugged southeastern border with Iraq before dawn on Wednesday, reports said. \"It is clearly unacceptable that Iraq\'s territory is being used to mount cross-border attacks against neighboring countries,\" the statement said. \"The sovereignty and territorial integrity of both Turkey and Iraq should be respected.\" \"The secretary-general urges Iraq and Turkey to engage in constructive dialogue in order to find a peaceful solution to this challenge,\" the statement said. Earlier on Wednesday, U.S. President Barack Obama and the European Union condemned the rebel attacks on the seven remote Turkish army outposts in the border area. The Turkish security forces responded with an offensive that killed 15 rebels of the outlawed PKK in the border area on Wednesday. Listed as a terrorist organization by Turkey, the United States and the European Union, the PKK took up arms in 1984 to create an ethnic homeland in southeastern Turkey.