Hill told reporters that the transfer involved "the total amount" of disputed North Korean funds, which he said was "something like $23m".

 

It is unclear why the amount was different from previously reported figures of $25m.

 

"I think this is the time when everyone needs to kind of quicken the pace and work very hard," he said.

 

Shutdown 'within weeks'

 

North Korea nuclear deal

On February 13, 2007, at six-nation talks in Beijing, North Korea agreed to:

 

Start shut down of main Yongbyon nuclear reactor facility within 60 days of deal

 

Allow UN nuclear inspectors entry for all monitoring and verification

 

Discuss list of all nuclear programmes and materials including plutonium extracted from fuel rods

 

Declare all nuclear programmes and disarmament of all existing nuclear facilities

 

Begin talks on normalising diplomatic ties with the US and Japan, and resume high-level talks with South Korea

 

In return US, Russia, China, Japan and South Korea promise initial shipment of 50,000 tonnes heavy fuel oil within initial phase

 

The five nations agreed to establish working groups for initial and full implementation of action plan

 

Additional aid up to the equivalent of 1m tonnes of heavy fuel oil to be delivered to North Korea upon compliance

"We're going to really have to pick up the pace if we're to get back on our timelines."

 

He added that he hoped to see a shutdown of the North's reactor at Yongbyon "within weeks, not months."

 

Hills comments came ahead of reports of a short-range missile test by North Korea, although he later dismissed suggestions that the test might have any political significance.

 

Under a deal reached in Beijing in February with China, Japan, Russia, South Korea and the United States, North Korea had pledged to shut down the reactor by the middle of April.

 

However, Pyongyang said it would not do so until the funds were unfrozen and it was able to transfer them out of Macau.

 

On Monday a Russian news agency cited an unidentified North Korean official as saying Pyongyang now plans to shut down the reactor in the second half of July.

 

Meanwhile the International Atomic Energy Agency, the United Nations' nuclear watchdog, has said it plans to send inspectors to North Korea next week, possibly as early as Monday.

 

They would discuss how to monitor and verify the shutdown of the Yongbyon reactor, under the terms of the February agreement.

 

Hill said he said he has been in contact with the IAEA and it understands the "need to move quickly."