TOKYO (Kyodo) -- The families and supporters of Japanese nationals abducted by North Korea decades ago reaffirmed Sunday their opposition to Prime Minister Shigeru Ishiba's plan to set up liaison offices in Tokyo and Pyongyang to resolve the long-standing issue.

The group held a meeting in Tokyo to formulate a policy for their future activities, claiming Ishiba's proposal would "only serve to buy time" amid growing concern that the aging and declining health of family members may hinder their reunion with abducted relatives.

Takuya Yokota, 56, the younger brother of Megumi Yokota, a symbolic figure among the Japanese abductees taken by North Korea in the 1970s and 1980s, said at a press conference following the group's gathering that it "strongly feels" Ishiba's vision is "unacceptable."

Its latest policy calls on the Japanese government not to provide humanitarian aid to North Korea, lift unilateral sanctions or try to normalize diplomatic ties before Pyongyang ensures the return of all abductees.

The families and supporters also urged Ishiba, who took office last October, to "take all necessary steps to hold a Japan-North Korea summit to pave the way for settling the abduction issue. North Korea asserts the issue has already been resolved.

In recent years, Japanese prime ministers have committed to meeting with North Korean leader Kim Jong Un without conditions, but negotiations between the two countries are believed to have stalled for around a decade.

On Sept. 17, 2002, then Japanese Prime Minister Junichiro Koizumi visited Pyongyang and signed a historic declaration with late North Korean leader Kim Jong Il, the father of Kim Jong Un.

Under the Pyongyang Declaration, the two Asian nations agreed to make "every possible effort for an early normalization of the relations," while Japan pledged to extend economic cooperation to North Korea after ties are established.

Koizumi also obtained North Korea's first formal apology for the abductions and five abductees were brought back to Japan. Tokyo still seeks the return of 12 others whom it has officially recognized as abductees.