North Korea's surprise promise to freeze its nuclear arms program is a positive development, but there is no guarantee it will live up to its word and the hermit state should take concrete action before resuming the six-party talks, the government and Japanese experts said Thursday.
Foreign Minister Koichiro Genba welcomed Wednesday night's declaration, a result of last week's U.S.-North Korea bilateral talks.
But he stressed that it is only one step forward in the long process of ending North Korea's nuclear quest, as demanded by Japan and other countries.