SEOUL, South Korea (AP) _ A U.S. Congressman said Monday that time was running out for North Korea to halt nuclear weapons development, and said he was greatly discouraged after talks with its leaders.

Meanwhile, North Korea on Monday welcomed President Roh Tae-woo's declaration that South Korea is free of nuclear weapons and said it will ''go through the relevant procedures'' to open its own facilities to international inspection.

Monday's statement, carried by the official Korea Central News Agency, quoted an unnamed Foreign Ministry spokesman as saying that the withdrawal of nuclear weapons from the South would be a ''a great victory for our nation.''

''If it is true that U.S. nuclear weapons have been completely withdrawn from South Korea and nuclear weapons no longer exist there as (Roh) had announced, we welcome this,'' it said.

The statement, monitored in Tokyo, was the North's first official response since Roh declared South Korea nuclear-free last week, stating in effect that U.S. nuclear weapons had been removed.

The United States and other major powers had expressed unease over intelligence reports that the hard-line Comunist state is nearing the ability to produce nuclear weapons of its own, and have been pressuring Pyongyang to allow international inspections.

Roh's announcement was seen as a first step toward satisfying the North's conditions for such inspections.

However, said U.S. Rep. Stephen J. Solarz, D-N.Y., ''North Korea seems more interested in avoiding a satisfactory resolution of the nuclear problem than in facilitating one.

''If the nuclear issue is not resolved,'' Solarz told a news conference, ''it could lead to grave consequences ... . I hope I am wrong. The clock is ticking. Time is running out.''

Solarz said he spent more than seven hours last week with North Korean leaders, including 2 1/2 hours with President Kim Il Sung, and left ''disturbed and dismayed.''

He said North Korean officials clearly indicated they did not take seriously a South Korean proposal for pilot inspections in both nations.

Solarz, chairman of the House subcomittee on Asian and Pacific affairs, was the first American politician to discuss nuclear issues with the North Korean leader since nuclear concerns escalated earlier this year.

The North Korean Foreign Ministry spokesman was quoted as saying that North Korea will sign a safeguards accord under the international nuclear non- proliferation treaty, thus opening the way for inspections, ''on the premise'' that the United States will confirm it has removed its nuclear arsenal from the South.

''Hearing only the words of the South Korean chief executive, one cannot properly understand if the nuclear weapons have been withdrawn or not,'' he said in the statement.

The United States has a longstanding policy of neither confirming nor denying the location of its nuclear weapons overseas.

North and South Korea have been bitter rivals since their peninsula was divided at the end of World War II in 1945 and the Korean War in the early 1950s.