Two former U-S officials say Washington should offer a security guarantee in return for North Korea's abandonment of its nuclear program.

Former national security advisor Brent Scrowcroft and ex-national security official Daniel Poneman made the remarks in a joint article to Thursday's Wall Street Journal.

They said the North has no reason to hurriedly return to the six-party talks because it knows diplomatic pressure will increase.

While snubbing the talks, the article said Pyongyang has strengthened its military capability and correspondingly its bargaining power, and this is why the United States must not simply wait for its return.

They also called inappropriate a naval blockade to prevent the North from exporting nuclear weapons.