Turkey's National Security Council will propose extending the state of emergency introduced after the failed coup in July, it said on Wednesday, a move expected since President Tayyip Erdogan floated the idea.

Erdogan announced the three-month state of emergency on July 20, saying it would enable authorities to take swift action against those responsible for the putsch, in which a group of rogue soldiers tried to topple the government and killed at least 240 people.

"To take precautions to protect the rights and freedoms of our citizens, our democracy and the principle of the rule of law, it was decided that an extension of the state of emergency should be proposed," the security council said in a statement.

It gave no details on the duration of the proposed extension.

Erdogan had said there would be no obstacle to prolonging the state of emergency beyond the initial three-month period. In the crackdown following the coup, some 100,000 people in the police, civil service, military and judiciary have been sacked or suspended. Another 40,000 people have been detained.

Turkey's Western allies and human rights groups have voiced disquiet about the extent of the crackdown, fearing that Erdogan is using the coup as a pretext to stifle dissent.

The government blames followers of Muslim cleric Fethullah Gulen for the coup and says the purges are necessary to root out Gulenist influence in the state.

Gulen, who has lived in self-imposed exile in the United States since 1999, has denied involvement in the attempted coup and condemned it.