North Korea has criticised the US's plan for a futuristic "Golden Dome" missile shield, saying it could "turn outer space into a potential nuclear war field".

The defence system, which President Donald Trump plans to unveil by the end of his term, is aimed at countering "next-generation" aerial threats to the US, including ballistic and cruise missiles.

Pyongyang's foreign ministry slammed the plan as "the height of self-righteousness [and] arrogance", state media reported.

It accused Washington of being "hell-bent... to militarise outer space" and warned that the plan might spark "a global nuclear and space arms race".

North Korea considers Washington an adversary and has routinely condemned joint military drills between the US and South Korea.

Pyongyang probably sees the Golden Dome as a threat that can "significantly weaken" its nuclear arsenal, Hong Min, a senior analyst at the Korea Institute for National Unification, told AFP news agency.

"If the US completes its new missile defence programme, the North will be forced to develop alternative means to counter or penetrate it," he said.

In 2022, the North passed a law declaring itself a nuclear weapons state, and it has tested a variety of ballistic and cruise missiles in recent years.

Early this year it claimed it fired a new intermediate-range ballistic missile tipped with a hypersonic warhead which it said "will reliably contain any rivals in the Pacific region".

North Korea joins China in criticising the US's plan. Beijing said last week that it is "seriously concerned" about the Golden Dome, which it said has "strong offensive implications".

"The United States, in pursuing a 'US-first' policy, is obsessed with seeking absolute security for itself," China's foreign ministry said. "This violates the principle that the security of all countries should not be compromised and undermines global strategic balance and stability."

Many analysts believe an update to the US's limited defence systems is necessary, but some warn the process of developing the Golden Dome could face technical and political challenges.

For one, its hefty price tag could suck up a large chunk of the US defence budget.

An initial sum of $25bn (£18.7bn) has been earmarked in a new budget bill - although the government has estimated it could end up costing 20 times that over decades.