By Rob Watson BBC Washington correspondent

The United States says agreement has been reached at the United Nations on a new system of sanctions against Iraq.

The US says the new sanctions will prevent Iraq obtaining weapons

The UN Security Council is expected to vote to approve the new arrangement formally by the end of the week.

This promises to be the biggest change in the UN sanctions against Iraq since the introduction of the oil-for-food programme in 1996.

Under the current sanctions regime, all Iraqi imports have to be approved by the Security Council first.

'Haggling'

But with the new arrangement, only those items on a list designed to keep out goods with potential military uses will face UN scrutiny.

That said, the list is 160 pages long.

The new agreement follows years of haggling among the UN's major powers and represents something of a victory for the US and Britain - because Iraq and its supporters in the Security Council, notably Russia, had wanted to see the sanctions lifted altogether.

The new arrangement will also serve as something of a propaganda coup as the US and Britain will now be able to argue there is no reason whatsoever why the Iraqi people should continue to suffer as a result of the UN sanctions.

But US claims that the new set-up will tighten controls over what, it alleges, are Iraq's efforts to build weapons of mass destruction are more questionable, as the new resolution does little to tackle enforcement of the now notoriously leaky sanctions.