When asked upon his arrival in Malaysia whether four other facilities had been shut down, the head of the UN nuclear watchdog replied: "We're in the process," leaving his sentence unfinished.

"I'll talk to you tomorrow morning," he added.

ElBaradei, who was to meet Malaysia's Deputy Prime Minister Najib Razak later Tuesday, has scheduled a press conference for Wednesday morning.

The IAEA chief confirmed on Monday during a visit to Bangkok that his inspectors had verified the shutting down of North Korea's nuclear reactor and were "working to verify the shutdown of the other four facilities."

He said the IAEA team hoped to check on those four installations by Wednesday, the day that six-party talks on the North's nuclear programmes are set to resume in Beijing.

The reactor shutdown is the North's first step since 2002 towards ending its nuclear programme, which culminated in an atomic bomb test last October, and the first phase of a six-nation disarmament deal reached in February.

The United States, South Korea and Japan -- parties to the six-nation talks with the North, China and Russia -- have expressed caution over the shutdown, saying it did not mean Pyongyang would easily give up its nuclear weapons.