ANKARA (Reuters) - Turkish Prime Minister Ahmet Davutoglu will return the mandate to form a government to President Tayyip Erdogan Tuesday evening after the ruling AK Party's coalition talks with opposition parties collapsed, an AKP official told Reuters.

Erdogan could dissolve Davutoglu's caretaker cabinet and call for the formation of an interim "election government" if no deal is reached by Aug. 23. That would mean power being shared between all four parties before a snap election in the autumn.