The United States revealed on Tuesday reports that North Korea may be preparing for another missile test hours after President Donald Trump tweeted that Trump said the US-led campaign of sanctions and other pressure were beginning to have a "big impact" on Pyongyang.
US Ambassador to the United States Nikki Haley told reporters at the UN in New York said that if reports of a new missile test are true, it would necessitate tougher steps against Pyongyang.
"I hope that doesn't happen. But if it does, we must bring even tougher measures to bear against the North Korean regime."
Earlier, Trump sounded open to the possibility of an inter-Korean dialogue after North Korean leader Kim Jong Un made a rare overture toward South Korea in a New Year's address.
He referred to the recent, dramatic escape of at least two North Korean soldiers across the heavily militarized border into South Korea. But he also alluded to North Korean leader Kim Jong Un's comments Monday that he was willing to send a delegation to the Winter Olympics, which will be hosted by South Korea next month.
"Soldiers are dangerously fleeing to South Korea. Rocket man now wants to talk to South Korea for first time. Perhaps that is good news, perhaps not - we will see!" Trump said, using his derisive moniker for the young North Korean leader.
In response to Kim's overture, South Korea on Tuesday offered high-level talks on January 9 at the shared border village of Panmunjom to discuss Olympic cooperation and how to improve overall ties.
North Korea did not immediately react to the South's proposal.
If there are talks, they would be the first formal dialogue between the Koreas since December 2015. Relations have plunged as the North has accelerated its nuclear and ballistic missile development that now poses a direct threat to America, South Korea's crucial ally.
The US administration, however, will be suspicious of any effort by Kim to drive a wedge between Seoul and Washington. Pyongyang could view a closer relationship with Seoul has a way for reducing its growing international isolation and relief from sanctions that are starting to bite the North's meager economy.