The widow of former President Kim Dae-jung has not heard back from North Korea, nearly a month after proposing talks to arrange a trip across the border, sources said Sunday.

Lee Hee-ho, the first lady while Kim served in office from 1998 to 2003, had been targeting late May for her visit, which, if realized, could help alleviate tension on the divided peninsula.

Kim Dae-jung remains respected in North Korea for his "sunshine" policy that actively pushed cross-border exchanges and reconciliation. After holding the first inter-Korean summit with the then North Korean leader, Kim Jong-il, in 2000, he was awarded the Nobel Peace Prize that same year. Lee had joined her husband on that trip to Pyongyang.

In April, the Kim Dae Jung Peace Center said it had suggested to its North Korean counterparts that the two sides should meet in Kaesong prior to Lee's trip. At the time, the North Koreans responded that they would be in touch with Lee's side, and insisted that Pyongyang's invitation to Lee still stood.

Last December, Lee sent a wreath of flowers to the North to mark the third anniversary of the death of Kim Jong-il. In a letter, Kim Jong-un, the late leader's son and successor to the throne, wrote that he was looking forward to hosting Lee in Pyongyang once the weather got warmer in the new year.

North Korea has yet to contact Lee, putting her May trip in doubt.

North Korea observers say Pyongyang appears reluctant to take steps to improve ties with Seoul because of pressing domestic issues.

The North's alleged purging of its defense minister, Hyon Yong-chol, for disloyalty and disrespect, may be tied with the situation.

"With senior officials getting forced out of power, hawkish voices will drown out softer ones," one source said, requesting anonymity. "This can affect inter-Korean relations." (Yonhap)