LONDON - British Foreign Secretary Philip Hammond and visiting U.S. Secretary of State John Kerry held talks on Saturday in London, showing different attitudes towards Russia' s involvement in the Syria crisis.

After the meeting at Hammond's official residence, Kerry said defense secretaries of the United States and Russia had held extensive talks via telephone on the fight against the Islamic State, according to local media reports.

Kerry, who is on his three-day visit to Britain, said "Would we welcome Russian help in going against Isil? Obviously. We have talked about it for some period of time."

"But the other part of the equation is Assad and how you resolve the fact that he is a magnet for foreign fighters to come to the region," he added.

The British government had been clear that if it is believed airstrikes in Syria were necessary it would go back to parliament for a vote, Hammond said.

"We keep that situation under continuous review and we will continue to talk to our allies about the military situation in the round," he said.

But Hammond said the situation in Syria becomes more complicated because of the Russian engagement.

"I think we need to discuss this as part of a much bigger problem: the migration pressures, the humanitarian crisis in Syria as well as the need to defeat Isil," he added.

Kerry described Russia's new focus on fighting IS militants as an opportunity to push toward a political settlement, BBC reported,  adding Kerry said the "root cause" of the current migrant crisis in Europe was the violence in Syria.(Xinhua)