Russia and Britain can overcome their differences on the Syria conflict, British Prime Minister David Cameron said after meeting President Vladimir Putin in London.
The conflict was at the top of the agenda in Sunday's meeting which could set the tone for the Group of Eight (G8) summit, with the West at odds with Moscow over how to handle the conflict.
Cameron said that he blamed President Bashar al-Assad for "tearing country apart" and the Syrian leader had to go.
But he said: "What I take from our conversation today is that we can overcome these differences if we recognise that we share some fundamental aims: to end the conflict, to stop Syria breaking apart, to let the Syrian people decide who governs them and to take the fight to the extremists and defeat them."
Putin fiercely defended Russia providing the Syrian regime with arms when asked if his nation had blood on its hands.
"You can't deny that both sides have blood on their hands. The question is who to blame," Putin said defiantly.
"You shouldn't back people who kill their enemies and film themselves eating their organs.
In-depth coverage of escalating violence across Syria
"Do you want to supply arms to these people? This goes against the humanitarian and cultural values that Europe has been professing for centuries."
Putin was referring to disturbing video footage on the internet which is said to be of one rebel fighter eating what appeared to be the heart of a government soldier.
The talks followed a decision by President Barack Obama's administration to arm rebels trying to overthrow President
Bashar al-Assad after it said it had obtained proof that the Syrian government had used chemical weapons.
The Russian leader, who arrived an hour late for the talks, said he wanted to help broker a peace deal for Syria and he
hoped that the G8 summit in Northern Ireland could help advance that process.
But Cameron said big differences over how to best achieve that aim remained between Britain and Russia.
"There are very big differences between the analysis we have of what happened in Syria and who is to blame but where there is common ground is that we both see a humanitarian catastrophe," Cameron said.
Al Jazeera's Tim Friend said that it was early days but Cameron and Putin could go to the G8 summit on Monday with something to build on when they meet Obama and other leaders.
"Perhaps this is just the beginning," Friend said.