Rep. Song Young-gil, leader of the ruling Democratic Party, blamed a flare-up in inter-Korean tensions on the uncertainty of US policy on North Korea, in comments delivered Sunday US time.

Song, who is visiting the US to discuss North Korea’s denuclearization with key White House officials and members of Congress, was referring to Pyongyang’s recent missile tests. The North revealed a new railway-borne missile system and launched ballistic missiles from a train in violation of UN resolutions.

“The US policy on North Korea is clearly neither the strategic patience nor the top-down approach,” Song told reporters, referring to the respective approaches of former US Presidents Barack Obama and Donald Trump.

The Biden administration is trying to reopen nuclear dialogue with North Korea as part of what it calls practical diplomacy, which many see as a middle ground between the policies of his two predecessors. North Korea has rebuffed the outreach, though it has not entirely shut the door to talks.

“That’s where we need to work on to revive the talks. I’m looking forward to discussing ways to do that with my colleagues here,” Song said, adding that the Biden administration should not return to Obama’s strategic patience policy but should instead seek a breakthrough by using whatever is left of Trump’s legacy.

One way to resume inter-Korean exchanges is to rebuild inter-Korean trust through exchanges, Song argued. But North Korea, which rejected China’s Sinovac vaccines, has not responded to South Korea’s repeated offer to work together on a COVID-19 response.

Meanwhile, President Moon Jae-in, who is attending the annual UN General Assembly in New York, is expected to ask for support for his peace efforts on the Korean Peninsula.

North Korea did not respond to Cheong Wa Dae, which had reached out to the regime for a meeting on the sidelines of the gathering to celebrate the 30th anniversary of UN membership for both Koreas.

The two Koreas saw a brief opportunity to revive the momentum for a thaw in late July, when the North reached out to the South to reconnect the hotlines. But they were back to a standoff when Pyongyang accused Seoul and Washington of ramping up tension with their annual military drills, which ended in late August.