US eyes increasing tactical nuclear weapons amid threats from Russia, China

• United States may deploy more strategic nuclear weapons. 
• Russia, China, Iran and North Korea share advanced missile. 
  
• US follows limit of 1,550 deployed strategic nuclear warheads.

The United States might need to deploy additional strategic nuclear weapons in the future to deter increasing threats from Russia, China, and other adversaries, according to a top White House official.

Pranay Vaddi, the top National Security Council arms control official, delivered a speech on Friday in which he discussed "a more competitive approach" to arms control.

He outlined a policy shift aimed at urging Moscow and Beijing to reconsider their rejections of United States' proposal for talks of limiting arsenals.

"Absent a change in adversary arsenals, we may reach a point in the coming years where an increase from current deployed numbers is required. We need to be fully prepared to execute if the president makes that decision," he told the Arms Control Association.

"If that day comes, it will result in a determination that more nuclear weapons are required to deter our adversaries and protect the American people and our allies and partners."

The US currently adheres to a limit of 1,550 deployed strategic nuclear warheads as outlined in the 2010 New START treaty with Russia, Reuters reported.

Moscow "suspended" its participation in the treaty last year over US's support for Ukraine, a move that Washington deemed "legally invalid".

Vaddi's statements come a year after National Security Adviser Jake Sullivan assured the same group that there was no necessity to increase US strategic nuclear arms deployments in response to the arsenals of Russia and China.

He also offered talks "without preconditions".

Vaddi emphasised that the administration remains "committed to international arms control and non-proliferation regimes" established to limit the spread of nuclear weapons.

But, he said, Russia, China and North Korea "are all expanding and diversifying their nuclear arsenals at a breakneck pace, showing little or no interest in arms control".

The three and Iran "are increasingly cooperating and coordinating with each other in ways that run counter to peace and stability, threaten the United States, our allies and our partners and exacerbate region tensions," he said.

Russia, China, Iran and North Korea are sharing advanced missile and drone technology, said Vaddi, citing Moscow's use in Ukraine of Iranian drones and North Korean artillery and missiles, and Chinese support for Russia's defence industries.