SECURITY, conflict prevention, and terrorism dominated talks at the G7 as the leaders addressed issues that included Islamic State (IS) in Iraq and Syria, and the ongoing conflict in Ukraine.

"I believe that the biggest challenge is the threat from Islamist extremism and violence," David Cameron told a press conference at the end of the summit. Britain is sending more soldiers to help train Iraqi troops, and will continue to support the Iraqi Prime Minister, Haider al-Abadi.

The US President, Barack Obama, said that coalition forces had "made significant progress in pushing back ISIL from areas which they had occupied", but "they are are nimble, they are aggressive, and they are opportunistic."

On Libya, the G7 leaders said that "the moment for bold political decisions has come." They urged tribal fighters to "work together to transform the aspirations that gave birth to the revolution into the political foundations of a democratic state".

Harsh words were directed at Russia, whose membership of the G8 was suspended last year over its involvement in Ukraine.

The Russian President, Vladimir Putin, had to make a decision, President Obama said. "Does he . . . continue Russia's isolation in pursuit of a wrong-headed desire to recreate the glories of the Soviet empire; or does he recognise that Russia's greatness does not depend on violating the territorial integrity and sovereignty of other countries?"

The EU's heads of state and government will discuss the sanctions when they meet for the European Council Summit later this month. The sanctions are set to expire in July, but may be extended.

The German Chancellor, Angela Merkel, who hosted the G7 in the Bavarian resort of Schloss Elmau, told journalists that the leaders agreed that they would "toughen the sanctions if the situation requires us to do so".

They condemned the recent increase in fighting, and urged Russia to stick to the Minsk peace agreement.