Joe Biden (Photo by EPA)

President Joe Biden shifted his stance on long-range strikes against Russia due to Donald Trump's election victory and North Korea's deployment of soldiers to Russia, Reuters reported, citing unnamed officials.

According to a senior U.S. official and two other sources, the deployment of North Korean troops to Russia was viewed in Washington as a "major escalation that demanded a response."

Granting permission for long-range strikes aims to signal to North Korea that military cooperation with Russia is unacceptable and to prevent Russian forces from pushing Ukrainian defenders out of the Kursk region, the senior official said.

While the Biden administration's decision might lead to further escalation, the official noted that Russia has not yet taken any action against Ukraine's allies.

Two other informed sources said Trump's election win increased pressure on Biden's administration, prompting relaxed rules on weapon use and new aid measures.

One of the sources said that allowing long-range strikes could "help to 'Trump-proof' parts of Biden's Ukraine agenda by strengthening Ukraine's position in case they lose U.S. support."