Turkey’s ruling party could face closure for a second time in less than a year as a top court begins to investigate allegedly fraudulent foreign donations in a case that could plunge the nation into prolonged political turmoil.

Although the investigations are preliminary and there is no formal case yet against the Justice and Development Party (AK), legal experts say that it would automatically be shut down if the court proved that it had taken embezzled money from the Germany-based Deniz Feneri (Light House) Foundation.

AK denies any links with the foundation, which has been accused by a Frankfurt court of siphoning off more than 18 million donations from devout Turks in Western Europe.

The Turkish investigation was fuelled by an unusually bitter and potentially damaging row between Recep Tayyip Erdogan, the Prime Minister, and Aydin Dogan, the Turkish media mogul, over the reporting of the court case in Germany and its potential government links.

The AK party, a loose alliance of former Islamists, free-market economists and social liberals, escaped closure narrowly in July over allegations of Islamism.

That case was the culmination of a six-year power struggle between AK and the self-styled secularist Establishment that has long held the reins of power in Turkey.

Now the renewed prospect of closure hints that the battle is far from over.

European Union and Turkish foreign ministers meet this week to discuss Turkey’s longed-for but now stagnant membership process, but in Turkey the battle for identity and power has all but overshadowed the excitement over accession.

Currently occupying Mr Erdogan is the row with Mr Dogan, whom he accuses of attempting to blackmail the Government after it refused to grant favours to other companies in the Dogan group, including permission to build luxury residences on the site of the Hilton Hotel.

The Prime Minister is threatening to follow up with revelations into the state of media corruption. Mr Dogan complains that Mr Erdogan is threatening the freedom of the press, and his many newspapers and television channels have gone into antigovernment overdrive.

The row has been fuelled by Mr Erdogan’s vitriolic speeches over the past few days, the slowing economy and allegations against AK party municipal administrations of corruption and of attempting to restrict alcohol during the Muslim fasting month of Ramadan.

NonDogan media hint at deeper forces at work. According to Etyen Mahcupyan, a columnist at the independent Taraf newspaper, the media row and possible consequent court case could all be in the spirit of an ultra-secularist plot to use social chaos, together with media and public pressure and a possible military coup, to oust the Government.

“That the [Dogan group] supports the State and the military has become so obvious over the past few years . . . and the psychological need for this Government to go continues,” Mr Mahcupyan wrote.

“The Prime Minister has noticed this and is fighting to secure his hold on power. On the surface it may be all about lighthouses and hotel gardens but deep down our subject is still a coup.”

Turkey was founded as a secular state 85 years ago and the powerful elite of the military, judiciary, bureaucracy and academia – close to top companies such as Dogan – has taken the role of guarding secularism. The military has staged four coups since 1960.

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