Turkey is to tighten security across the country, and especially the capital, following a car bombing that killed 28 people in Ankara this week, Prime Minister Ahmet Davutoglu said on Saturday.

Davutoglu also said, in a briefing to reporters broadcast live on television, that the Turkish Kurdish militant group TAK had claimed the attack as a "proxy" to shield the Syrian Kurdish YPG militia.

He urged Turkey's NATO ally Washington to see any attack on Turkey as an attack on the United States.