"Russia launched a satellite into low Earth orbit that we assess is likely a counter-space weapon presumably capable of attacking other satellites in low Earth orbit," Pentagon spokesman Air Force Major General Pat Ryder told a press briefing late Tuesday.

The Russian "counter-space weapon" launched on May 16 was deployed "into the same orbit as a US government satellite," he said.

Ryder added that Washington would continue to monitor the situation and was ready to protect its interests.

"We have a responsibility to be ready to protect and defend the domain, the space domain, and ensure continuous and uninterrupted support to the Joint and Combined Force," he said.

Earlier Tuesday, Moscow accused the United States of seeking to place weapons in space after Washington vetoed a Russian non-proliferation motion at the United Nations.

"They have once again demonstrated that their true priorities in the area of outer space are aimed not at keeping space free from weapons of any kind, but at placing weapons in space and turning it into an arena for military confrontation," Russian foreign ministry spokeswoman Maria Zakharova said in a statement.

The world powers have traded multiple accusations of seeking to weaponize space in recent months.

They have proposed rival non-proliferation motions at the United Nations as part of the spat.

Russia vetoed the US initiative last month, while Moscow's proposal was blocked by the United States, Britain and France in a vote on Monday.

US envoy Robert Wood said Russia's proposal, which called on all countries to "take urgent measures to prevent for all time the placement of weapons in outer space", was a distraction and accused Moscow of "diplomatic gaslighting".

He said that Russia's "likely" counter-space weapon was "presumably capable of attacking other satellites in low Earth orbit".

"Russia deployed this new counter-space weapon into the same orbit as a US government satellite," he said in remarks ahead of Monday's vote.

"Russia's May 16 launch follows prior Russian satellite launches likely of counter-space systems to low Earth orbit in 2019 and 2022."

In February, the White House said Russia was developing an anti-satellite weapon, the existence of which was confirmed after lawmakers warned of an unspecified but serious threat to national security.