"We understand the worry of Turkish authorities in the face of a wave of recent terrorist attacks," foreign ministry spokesman Mikhail Kamynin said in a statement.

"At the same time ... we call on the parties to the conflict to demonstrate maximum restraint and to consider all possible consequences of their actions in the long term."

Kamynin warned that a Turkish incursion into Iraq could have "negative consequences in the long term for security and stability in a wide regional context."

The caution came after Turkish Prime Minister Recep Tayyip Erdogan said in Ankara that the his government was considering seeking parliamentary approval for an incursion into northern Iraq against Kurdish rebel bases.

"The preparations for a motion have started and are continuing," the Anatolia news agency quoted Erdogan as saying.

Under Turkish law, parliament must authorise any deployment of Turkish troops abroad.

The motion could be submitted to parliament as early as next week, political sources said.

Exasperated by mounting separatist Kurdish violence and Iraqi inaction against rebel bases, Ankara said Tuesday it would employ all measures, "including a cross-border operation if necessary," to combat the Kurdistan Workers' Party (PKK).

Ankara says the PKK, listed as a terrorist group by Turkey and much of the international community, enjoys free movement in northern Iraq and obtains weapons and explosives there for cross-border attacks in Turkish territory.