Obama in London.

Barack Obama has made it to London after a lengthly world tour. Obama said he had a "terrific" conversation after a walk-about with the Prime Minister.

On the wars the coalition are fighting in Afghanistan and Iraq, Obama said: "I know that the troops here in Great Britain have borne a heavy price for wars in both Iraq and Afghanistan and I think the American people are grateful for all the help that has been provided."

This was largely a photo-op for both men. tBg just hopes Obama didn't give any tips to Gordon Brown on how to enthuse a crowd of 50,000 people, or adjust language/rhetoric so to inspire the millions watching.