A BALANCE OF POWERS:

An investigation into senior members of Turkey's ruling AK party marked the latest fallout from a widening rift between the country's president, Recep Tayyip Erdogan, and his handpicked successor, Ahmet Davutoglu.

The tension between the two men has injected an unusual element of internal strife into the long ruling AK party, and poses a threat to Mr Erdogan's gambit to consolidate his sway over the country after June 7 general elections.

"There is a power struggle between Erdogan and Davutoglu," says Ahmet Hakan, a well-known Turkish commentator. "Erdogan says: 'I want control', while Davutoglu says: 'I am the prime minister and I want to use my powers.' "

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