A top Russian parliamentarian said on Tuesday that North Korea will hold nuclear tests in June and assessed the situation with the rogue state’s nuclear program as “near the critical point”.

The head of the State Duma’s International Relations Committee, Konstantine Kosachev, was quoted by the RIA-Novosti news agency as saying that “there are all grounds to think that a test of a nuclear device can take place in DPRK in June”. The politician made this statement before leaving for Pyongyang on a visit.

<##IMAGE##>Also on Tuesday Reuters quoted South Korea’s Chosun Ilbo newspaper as saying that U.S. intelligence has detected the movement of heavy equipment in North Korea that points to possible preparations for an underground nuclear test.

The newspaper, quoting a government source, said U.S. spy satellites had captured frequent movements of trucks in the north-eastern region of Kilju, as well as the movement of cranes and other heavy equipment into the area.

“U.S. intelligence authorities believe the images and other information point to preparations for a possible underground nuclear test,” the source was quoted as saying.

U.S. and Japanese news reports last week said Washington had warned some governments and agencies that North Korea could be preparing for a test, which would represent a serious escalation of tensions over North Korea’s nuclear weapons ambitions.

U.S. and South Korean officials have since denied there were definitive signs of an imminent test. On Tuesday Seoul shot down the latest report, with Defense Minister Yoon Kwang-ung telling reporters before a Cabinet meeting there were no unusual indications in the area.

A Defense Ministry official told Reuters there also was no foundation to the Chosun Ilbo report that the U.S. intelligence was passed on to the South Korean government.

He said a project to dig a tunnel had been detected in the same area in the late 1990s and the two countries had been watching it closely, without any sign of preparations for a test.

“It is not clear what the purpose of the tunnel is,” the official added.