Inspectors from the UN Monitoring, Verification and Inspection Commission (UNMOVIC) and the International Atomic Energy Agency (IAEA) must be allowed to go back to Iraq, the Russian foreign ministry said in a statement.

"We believe that these organizations, which possess all the necessary expertise to that end, must as soon as possible receive unlimited access to Iraq's nuclear sites to resume their interrupted task," foreign ministry spokesman Alexander Yakovenko said in the statement.

"It is essential that Iraq's transitional government and the United States adopt urgent measures to establish control over sensitive material and equipment, and allow international organizations specially authorized to do that to accomplish their task without any obstacles," Yakovenko added.

IAEA director general Mohamed ElBaradei earlier this month told the United Nations that equipment and materials that could be used to make nuclear weapons, in some cases entire buildings housing sophisticated technology, were disappearing from Iraq.

In a letter to the Security Council, ElBaradei said he was concerned about the "widespread and apparently systematic dismantlement that has taken place at sites previously relevant to Iraq's nuclear program" under ousted dictator Saddam Hussein.

So-called dual-use equipment -- which has peaceful as well as weapons-making applications -- is disappearing, ElBaradei said.

IAEA inspectors have made two brief trips since the US-led war on Iraq war ended in April 2003 to check inventories at the Tuwaitha nuclear complex south of Baghdad but these were in response to looting and not part of weapons inspections under the agency's UN mandate.

The IAEA is ready to send inspectors back to Iraq, a spokesman said Wednesday.