Western diplomats accuse President Recep Tayyip Erdogan of failing to show wholehearted support for the battle against ISIL militants, although Turkish officials bitterly reject these claims.
Ankara had said its hands were tied while trying to save the lives of 49 Turks, including diplomats and children, who were taken hostage by the ISIL group in June in Mosul.
Even with the release of the hostages on Saturday it was unclear whether Turkey would now change course.
Many analysts say it was Turkey's policy -- spearheaded by then foreign minister now Prime Minister Ahmet Davutoglu -- of supporting extremist terrorists in Syria.
"Turkey bears a direct responsibility for the rise of ISIL and is terribly embarrassed today," said Marc Pierini, a scholar at Carnegie Europe and former EU ambassador to Turkey.
"Until the past few months, access to Turkish territory was wide open to them. This has changed today under pressure from the West and also because the government has realized now, pretty late I must say, that ISIL could also be a direct threat to Turkey."
Erdogan this week angrily rejected claims Turkey encouraged ISIL, saying it was an "impertinence" to suggest Ankara supported terror.