The International Atomic Energy Agency (IAEA) has called on North Korea to secure transparency in its nuclear activities and to return to the nuclear Non-Proliferation Treaty (NPT).

The U.N. nuclear watchdog's Board of Governors issued the call in a statement after discussing North Korea's nuclear issue in Vienna on Tuesday.

The statement expressed concern over Pyongyang's failure to implement measures requested by the IAEA after the communist state withdrew from the NPT in January of last year.

In the statement, the board also voiced hope that the six-nation nuclear talks would reap substantial results in resolving the North's nuclear standoff.