“Power corrupts. When Erdogan became prime minister in 2003, he still wanted to curb corruption in the country. Today, it is more rampant than ever,” Davutoglu said in an interview with Der Spiegel published on Tuesday.

Erdogan's government has faced accusations of widespread corruption and links to the Mafia in a series of YouTube videos and tweets published over the past three months by underworld figure Sedat Peker, who fled the country to an unknown location after Turkish prosecutors sought his arrest. His government regularly awards lucrative state construction contracts to a small clique of businessmen.

Davutoglu, who served as foreign minister between 2009 and 2014 and prime minister from 2014 to 2016, said he sought to battle corruption and rising authoritarianism during his tenure as prime minister. He said he left the governing Justice and Development Party (AKP) to form the opposition Good Party in 2019 after the introduction of a presidential system in 2018, his proposals to reform Turkey’s democracy were rejected, and political pressure on him from within the AKP grew.

“I wanted to fight nepotism, but my efforts were in vain. After I left office, Erdogan's son-in-law became the most powerful man in the system. I stood up for ethics in politics. Erdogan didn’t want that,” he said.

Davutoglu said Turkey’s courts should have launched an investigation “long ago” into the claims of Peker, and police and prosecutors need to follow up on his accusations.

“As a matter of principle, cases of corruption and abuse of power must be investigated by independent courts,” he said.

“An investigative commission should also be formed in parliament. But none of that is happening. Erdogan has remained silent on the allegations for weeks. This government is incapable of responding to crises.”

Turkey is now in a crisis that is deeper than financial turmoil that swept the country in 2001, which helped Erdogan's AKP win elections the following year, Davutoglu said.

“It isn’t just the economy that is affected, but also the very foundations of the state,” he said. “But I’m still convinced that we can find our way out of this low point if we can succeed in restoring democratic principles and renewing our institutions.”

Turkey is due to hold presidential and parliamentary elections in 2023. Davutoglu said he expected the elections to be brought forward to as early as the spring of next year due to the fragility of Erdogan's alliance with a far-right nationalist party.

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