But Iran's co-operation has limits.

ECONOMIST: Distrust, in all around | The

But the Scottish Salmon Producers Organisation says the Scottish Environment Protection Agency assesses farms before and during operation, and sets limits on the use of chemicals and allowed pollution.

BBC: How can Scotland cope with China's salmon demands?

Even Mr Blunkett now concedes that co-operation with America has its limits.

ECONOMIST: A setback for the government's anti-terrorism measures

But there are limits to co-operation.

ECONOMIST: The drug war

"We found a trading operation that piled on risk, ignored limits on risk-taking, hid losses, dodged oversight and misinformed the public, " said Carl Levin, the subcommittee's chairman.

BBC: Sign outside JPMorgan offices

"We found a trading operation that piled on risk, ignored limits on risk-taking, hid losses, dodged oversight and misinformed the public, " said Carl Levin, the subcommittee chairman, who is a Democrat.

BBC: JP Morgan accused of hiding losses by Senate report

Pretty much all of the French candidates have tried to mark themselves out with voters by defining new limits on international co-operation and by emphasising that France, as a great and historic nation, can keep certain international forces at bay.

BBC: Nationalism looks set to remain on trend in France

Its biggest hammer is a policy that limits foreign multinationals to 50% ownership of any manufacturing operation in the country.

FORBES: Thanks, Now Move Over

In this case, the Position Limits Rule, which according to both parties is a significant and unprecedented change in the operation of the commodity derivatives market, has not yet gone into effect.

FORBES: Dramatic Federal Court Ruling Vacates CFTC Positions Limit Rule