Iraq's top Shiite cleric Grand Ayatollah Ali al-Sistani on Friday criticized the deployment of Turkish troops and tanks to the country's north that Baghdad says took place without its approval.

Iraq has demanded that Ankara remove the newly-deployed forces, which were sent to a base near the city of Mosul, but Turkey has pushed for them to stay.

President Recep Tayyip Erdogan has said Turkish troops deployed in Iraq for training purposes in the fight against the Islamic State were not on combat mission and their pullout was "out of the question."

The deployment of several hundred troops by Turkey in Bashiqa, close to an area held by IS in northern Iraq, has enraged Baghdad which has asked Ankara to withdraw all its forces.

Tensions between Washington and Moscow gave way to a fiery exchange at the State Department Thursday, with a spokesman accusing a Russian television journalist of asking "absolutely crazy" questions.

Spokesman John Kirby chided Gayane Chichakyan of state-backed RT for posing "absolutely ridiculous" questions as she persistently queried him about the U.S. position on Turkey's military deployment in Iraq during the State Department's usually cordial daily briefing.

Turkish prosecutors Thursday demanded 35-year jail terms for two alleged people-smugglers blamed for the death of a three-year-old boy whose beached corpse came to symbolize Syria's refugee crisis, local media reported.

The suspects, both Syrians, stand accused of "causing death by deliberate negligence" and "migrant smuggling" after five Syrian refugees including Kurdish toddler Aylan Kurdi died when their boat sank in September while on its way to Greece, state-run Anatolia news agency reported.

Russian President Vladimir Putin on Wednesday invited British experts to help analyze the black box of a warplane downed by Turkey, as he discussed the Syria crisis with British Prime Minister David Cameron.

"Vladimir Putin invited British specialists to take part in decoding flight data recorders of the downed Su-24," the Kremlin said after the phone talks with Cameron.

Turkish Prime Minister Ahmet Davutoglu said Tuesday his government was considering retaliatory measures against Moscow, with whom it is embroiled in a bitter dispute over Ankara's shooting down of a Russian warplane.

"If we find it necessary, we will introduce retaliatory sanctions," Davutoglu told members of his ruling Justice and Development Party (AKP), adding that cabinet had discussed possible measures at a meeting on Monday.

At least six children died Tuesday when a boat carrying Afghan migrants sank in Turkish waters while on its way to Greece, local media reported.

The Turkish coastguard recovered the bodies of the children, including a baby, and were still looking for two other migrants reported missing, the official Anatolia news agency said.

Turkish Foreign Minister Mevlut Cavusoglu on Saturday called for dialogue with Russia to overcome tensions after the downing of a Russian warplane near the Syrian border for alleged violations of Turkey's airspace.

"Of course we have different views but we need to continue to talk in order to narrow our differences," Cavusoglu was quoted as saying by the state-run Anatolia news agency.

Baghdad demanded Saturday the immediate withdrawal of forces it said Turkey illegally deployed in Iraq, which is struggling to assert its sovereignty while receiving foreign assistance against the Islamic State group.

A senior officer from the Kurdish forces in the region -- which are allied to Ankara -- downplayed the deployment as a routine training rotation but a Turkish paper said it was part of deal to set up a permanent base.

Recep Tayyip Erdogan and Vladimir Putin, leaders with remarkable similarities who built a new era of cooperation between Turkey and Russia, have suffered a ferocious falling-out that will harm relations for years to come.

The two presidents, who forged a strong friendship in over a decade in power, have traded a slew of insults since Turkey shot down a Russian warplane on November 24 on the Syrian border for alleged repeated violations of its airspace.