The White House on Friday said North Korea recently provided Russia with a shipment of weapons, raising concerns about the expanded military relationship between the two countries.
The White House showed a series of satellite images that it said indicate cargo from an ammunition depot in North Korea (DPRK) was loaded on to a Russian-flagged ship and then taken by rail to a depot near Russia's southwestern border. The delivery took place between September 7 and October 1, the US said.
North Korean leader Kim Jong Un and Russian President Vladimir Putin met for a rare summit last month at which they discussed military matters, the war in Ukraine and possible Russian help for the secretive state's satellite programme.
In return for support, North Korea is seeking military assistance from Russia, including fighter aircraft, surface-to-air missiles, armoured vehicles and other advanced technologies, Kirby said.
The US is closely monitoring whether Moscow will deliver the weapons, but early signs of Russian ships offloading materials in North Korea may represent initial deliveries, he added.
The US said it will continue to enforce sanctions and make the case at the United Nations that the actions violate security council resolutions.
A ceasefire deal between Israel and Hamas in the Gaza Strip took effect on Sunday after a nearly three-hour delay, pausing a 15-month-old war that has brought devastation and seismic political change to the Middle East.
At least 86 people were killed and more injured in northern Nigeria on Saturday when a petrol tanker truck overturned, spilling fuel that exploded, the country's national emergency agency said.
Hundreds of supporters of South Korea's arrested president, Yoon Suk Yeol, stormed a court building early on Sunday after his detention was extended, smashing windows and breaking inside, an attack the country's acting leader called "unimaginable".
Russian forces unleashed a combined drone and missile strike on the Ukrainian capital Kyiv early on Saturday, killing three people in a central district, officials said.