Kivrikoglu, the army chief of staff says Islamists have penetrated official positions at every level.

Mr Sezer is a known secularist, and was expected by the government to approve the bill without question.

The president has however argued that such a measure should be backed by parliamentary legislation, and early in August he sent the decree back to the government saying it was unconstitutional, provoking the anger of Prime Minister Bulent Ecevit.

Concerns over what is and what is not constitutional have not troubled the Turkish military in the past.

"The army expels this kind of people as soon as it detects them. If [the government] wants public offices to function properly it should do the same," Huseyin Kivrikoglu, chief of the army's general staff, has said.

Islamists, along with separatist Kurds, are identified by the military as serious threats to Turkish stability.

Islamist government

Turkey's main Islamic political party, Welfare, was banned in August 1998. It was the biggest party in parliament, and in the general elections in December 1995, it took more than 20% of the vote.

The following year, Welfare leader Necmettin Erbakan became the country's first Islamist prime minister, as part of a coalition government.

Mr Ecevit (foreground) has the backing of the military

But Mr Erbakan's rule proved short-lived, when Turkey's military grew increasingly angered by what it saw as Welfare's attempts to Islamise the country, accusing the party of secretly planning to introduce Islamic rule.

Less than a year after he took office, Mr Erbakan was forced to resign under pressure from the military.

Though actual military coups in Turkey appear to be a thing of the past, the military still has a decisive role to play in the running of the country.

EU watches

On paper, Mr Ecevit's current government has the parliamentary majority needed to pass whatever legislation it wants to. But in reality, it is not clear that the proposals will be supported by all of the government coalition's MPs.

With an eye on Turkey's application to join the European Union, the government and military may have to take a softer approach on this issue.

The European Union has made it clear that real movement on constitutional change and improvements in Ankara's human rights record are a prerequisite to joining.

The European Commission is hoping to finalise an accession partnership with Turkey by the end of this year.