Russian President Vladimir Putin and UK Prime Minister Tony Blair have held talks over greater co-operation between Russia and the European Union.
Mr Putin met the Belgian leader Guy Verhofstadt earlier on Monday
European Commission President Jose Manuel Barroso was also present at the meeting, which discussed energy, trade and co-operation against terrorism.
"This is a relationship in economic terms that can only grow and prosper and strengthen," said Mr Blair.
The London talks come as Britain holds the presidency of the European Union.
"We want to work to take the relationship between Europe and Russia to a new and more intense and strengthened level," said the UK prime minister.
Russia and the EU have disagreed on issues such as Chechnya and Iran.
Mr Barroso said it was made clear to Mr Putin that the human rights situation in the region was being watched closely.
"We expressed as frankly as possible. We have said what we think," he said.
"It is important that Russia respects the human rights and when we mean respect the human rights we believe it should be in respect of our standards. The human rights we have in European Union and European Union member states."
The EU and Russia have also disagreed over Iran's nuclear power development program.
Another sticking point has been the lingering conflicts in the former Soviet republics which now lie between Russia and an expanded EU.
Soon Russia is expected to be supplying 50% of the EU's natural gas needs.
Mr Blair said: "Our economic future is now bound up together. But it was always going to be.
"You know the fact that Russia is a key exporter of energy to the EU is not something that suddenly happened in the last year, its been happening for many years.
"But actually with the right relationship that is a tremendous benefit to the EU."
President Putin looked to reassure those who may be worried about an increasing dependence upon Russia's natural resources.
"Russia is a reliable partner and never...failed her counter-partners in Europe," he said.
Mr Blair discounted any suggestion that reliance upon Russian energy supplies might encourage Europe to mute its criticism of internal developments in Russia.
This was, he said, a relationship of mutual interest, not dependence.
Mr Putin said that Russia had been constantly augmenting the supply of oil, helping the world economy, including Europe, by constraining prices,
"Without the contribution of Russia to the energy effort, prices would have been much higher," he said.
Mr Putin is also expected to present Russian state awards to British sailors who helped rescue Russian seamen trapped aboard a sunken submarine.