( Sky ) - Turkey has started building up its forces on the border of Iraq following more attacks by Kurdish militants.
The army was given the green light by the government to "take all necessary measures" against Kurdish rebels held responsible for two recent bomb attacks.
It is thought the Turkish army is planning a cross-border raid to strike bases where the rebels are believed to be hiding in northern Iraq.
An invasion could affect Turkey's ties with the United States and disrupt one of the few relatively peaceful areas of Iraq.
In the past, Turkey has carried out smaller-scale "hot pursuit" operations in Iraq that officials said did not require parliamentary approval.
Sky's Foreign Affairs Editor Tim Marshall said: "We have seen these build-ups of troops before.
"The Turkish military is incredibly angry about the PKK launching attacks out of Iraq and into Turkey.
"They are straining at the leash. But Recep Tayyip Erdogan's government appears very cautious. The Americans are also urging restraint."
However, he said America's intention to officially recognise the killing of Armenians by Turkish forces during the First World War as genocide - to Ankara's fury - could mean Turkey is less inclined to bow to US objections than it might be otherwise.
Meanwhile, Iraqi Kurds, who run a virtual mini-state in the north of the country, have vowed to defend their territory.
And an Iraqi Kurdish regional government spokesman, Jamal Abdullah, called on Turkey to show restraint.
He said: "Such attacks will threaten stability not only in Iraq but the whole region."
In the past 10 days more than two dozen people - soldiers and civilians - have been killed in southeastern Turkey in attacks by the Kurdistan Workers' Party - the PKK.
The group, labelled a terrorist organisation by Washington and the European Union, has been fighting Turkish forces since 1984.
Tens of thousands of rebels, soldiers and civilians have died.