MOSCOW: Russian President Vladimir Putin on Friday offered Iraqi Prime Minister Nuri al-Maliki Moscow's total backing for the fight against jihadist fighters who have swept across the Middle East country.

"Putin confirmed Russia's complete support for the efforts of the Iraqi government to speedily liberate the territory of the republic from terrorists," the Kremlin said in a statement following a phone call between the two leaders.

Maliki, increasingly under pressure at home and abroad, told Putin about steps the Iraqi government was taking to turn back a lightning offensive by the radical Islamic State of Iraq and the Levant (ISIL), that has overrun swathes of northern and central Iraq.

"It was noted that the activities of extremists conducting military operations on the territory of Syria has taken on a cross-border character and now threaten the security of the whole region," the statement said.

The conversation came after US President Barack Obama stopped short of acceding to Maliki's appeal for air strikes against the Sunni Muslim insurgents, prompting neighbouring Shiite Iran to charge that Washington lacked the "will" to fight terror.

On Friday the Kremlin's top foreign policy advisor Yury Ushakov told journalists that Putin would soon hold phone talks with Obama, in part, about the situation in Iraq.

Russia has blamed the latest violence sweeping Iraq on the 2003 US-led invasion of the country and said that any strikes on jihadist forces would have to be authorised by the United Nations.

Russia is one of the staunchest allies of Syrian strongman Bashar al-Assad and has helped prop up his regime during three years of fighting against a hotchpotch of rebel groups, including the ISIL.