The US and China say they have made progress on a draft UN resolution to harden sanctions on North Korea, after its rocket launch and nuclear test.
China's Foreign Minister Wang Yi and US Secretary of State John Kerry said a draft could soon be ready for approval.
Although China condemned North Korea's actions, it has always been reluctant to endorse sanctions that could threaten its neighbour's stability.
February's long-range rocket launch followed a nuclear test in January.
Both were widely condemned as a flagrant violation of UN resolutions and led to emergency sessions of the UN Security Council, where powers agreed to work towards toughening sanctions.
"Important progress has been made in the consultations and we are looking at the possibility of reaching agreement on a draft resolution and passing it in the near future," Mr Wang told a press conference after talks in Washington.
Mr Kerry added that if the draft resolution is approved it will go beyond anything the UN has previously passed.
The North insists it was merely launching a satellite and that its space programme is purely scientific in nature, but the US, South Korea and even its ally China say such rocket launches are aimed at developing inter-continental ballistic missiles.
Shortly after the launch, South Korea signalled its intent to begin discussions with the US on the deployment of a missile defence system to counter the threat from the North. The US also tightened its own sanctions.
The North's nuclear test in January, which it claimed was a test of hydrogen bomb technology, was its fourth since 2006. Its claims remain unconfirmed, with many experts expressing scepticism that North Korea can make a nuclear weapon small enough to fit on a missile.
Analysts say that the tests may indeed have been part of an effort by North Korean leader Kim Jong-un to bolster his authority and standing ahead of a landmark party congress expected to take place later this year.