BBC News with David Austin.

Drug enforcement officers in the United States say they have arrested more than 2,000 people in a lengthy investigation targeting Mexican trafficking rings. They said the joint operation also involving the FBI, the Mexican government and other American agencies has lasted almost two years and culminated on Wednesday with more than 400 arrests across 16 states. The Assistant Secretary and Director of Customs Enforcement at the Department of Homeland Security John Morton said the United States was serious about tackling the problem of drug crime.

"We face a serious, sustained challenge along our border with Mexico. The drug cartels and their brethren, the ailing smugglers, the money launderers, the gun traffickers all make a living, violating US and Mexican law on a daily basis. It's a violent business, it's a corrupt business. It's a business that demands our full attention. As you see here, it has our full attention."

The American State Department says the oil spill in the Gulf of Mexico caused by the British energy giant BP is not a source of tension between the two countries. Some American politicians have suggested BP should be forced to suspend dividend payments until it's clear that the oil giant is able to cover all possible compensation claims for the disaster. Earlier, the British Foreign Secretary William Hague said he didn't think there was anything anti-British about the American response. The Deputy Prime Minister Nick Clegg had a similar message.