On March 20, 1995, some 35,000 Turkish troops launched an invasion into Northern Iraq. The effect of the attack was however relatively limited, despite high PKK casualties, as the majority of the PKK forces left the region before the offensive begun as they had noticed the military buildup on the border and were anticipating the offensive. By April 25, Turkey pulled out 20,000 of its 35,000 troops. After on May 3, the Kurdistan Democratic Party delegation to Turkey said they would stop PKK activities in Iraqi Kurdistan, Turkey withdrew its remaining forces on May 4. The military operation strained relations between Turkey and the United States and Europe as over 15,000 Iraqi Kurdish civilians were displaced by Turkish forces.