Syria conflict: Kerry and Hammond seek negotiations.
Mr Kerry is on a European tour which is expected to be dominated by the Syrian conflict.
After talks with his UK counterpart Philip Hammond on Saturday, he said they "agreed completely on the urgency of nations coming together in order to resolve this war that has gone on for much too long".
US Secretary of State John Kerry has called for a renewed diplomatic effort to end the conflict in Syria.
Just as importantly, perhaps, a series of defeats for Syrian President Bashar al-Assad has made his position look more precarious than it has for years, possibly enough to shift the stalemate and bring the Syrian government to genuine negotiations.
Speaking after talks in London, he said what he described as Russia's new focus on fighting Islamic State militants could be an opportunity to push towards a political settlement. He said this was all the more urgent as violence in Syria was the "root cause" of Europe's current migrant crisis.The EU, which is divided on the issue, is to hold emergency talks next week.