Turkish protesters hold a lantern symbolising the victims of the Gezi Park protests that started in May, during a demonstration in Istanbul late on Tuesday. Protests were sparked in May in
opposition to the government’s plans to develop Istanbul’s Gezi Park into a complex with a mosque and shopping centre. Seven people lost their lives as a result of the protests.

Prime Minister Recep Tayyip Erdogan urged Turks to rally around him in fighting what he termed a dirty plot by foreign-backed elements targeting “the bread on your table, the money in your pocket, the sweat of your brow”.

“History will not forgive those who have become mixed up in this game,” Erdogan said in a televised end of year address devoted almost entirely to a corruption investigation he says has been engineered in police and judiciary to undermine his government and sap its influence in the Middle East and beyond.

Police raided offices and homes and detained businessmen close to the government and the sons of three ministers on December 17.

Erdogan responded by purging some 70 officers connected with the inquiry and blocking a second investigation into big infrastructure projects promoted by the prime minister.

“I invite every one of our 76mn people to stand up for themselves, to defend democracy and to be as one against these ugly attacks on our country,” he said.

The scandal poses the biggest challenge to Erdogan in 11 years as leader, raising fears of a fracture in his AK Party in the run-up to elections and damage to strong economic growth.

It also pitches him against a US-based Turkish cleric with strong influence in the police and judiciary, accused by Erdogan’s backers of conniving at the investigation. The former ally, Fethullah Gulen, denies the allegation.

Erdogan, who has won three elections, casts the scandal as a campaign by domestic dark forces and foreign financial organisations, media and governments resentful of a foreign policy more independent of Nato and the US.

Foremost in his suspicions is Gulen, who has no political party but great influence in key state institutions based widely on his global network of private schools and media.

Though their differences are not argued in public, the two have differed over foreign and domestic policies and the fate of the schools which Erdogan recently moved to close down.

“Circles uncomfortable with Turkey’s successes, its growing economy, its active foreign policy, its global-scale projects, implemented a new trap set against Turkey,” Erdogan said, sitting at a desk before the red Turkish national flag.

Erdogan said June anti-government protests across Turkey, triggered by a heavy-handed police crackdown on a demonstration against plans to redevelop Istanbul’s central Gezi Park, were part of the same conspiracy. “Just as the Gezi incidents were dressed up in the cover of trees, parks and the environment, the December 17 plot was hidden in the cover of corruption.”