North Korea's top diplomat in Moscow says Pyongyang is ready to rejoin the six-way talks on its nuclear program once Washington retracts what he called 'offensive' rhetoric against the North.

Ambassador Pak Ui-chun said Thursday the North is willing to return to the negotiating table once "necessary conditions are met."

Pak said that North Korea-Russia ties are witnessing continuous development, adding that the two countries will make significant contributions to creating multilateral order in the international community by strengthening bilateral cooperation.

The United States rejected North Korea's demand for an apology for Secretary of State Condoleezza Rice's characterization of Pyongyang as an "outpost of tyranny."

North Korea also reacted angrily when U.S. President George W. Bush had infamously branded the Communist country as part of an "axis of evil" along with Iran and pre-war Iraq three years ago.