State news agency says decision is direct challenge to the Singapore summit with nuclear talks at a standstill.

North Korea has criticised the US move to extend sanctions as an act of hostility and an outright challenge to the historic summit between the two countries’ leaders that was held in Singapore last year, Pyongyang’s state media said on Wednesday.

The White House last week extended by a year six executive orders related to sanctions imposed over North Korea‘s nuclear and missile programmes.

An unidentified North Korean foreign ministry spokesman called the move a “manifestation of the most extreme hostile acts” in a statement carried by the Korean Central News Agency, the official news agency.

The comments come two days after state media reported North Korea’s leader Kim Jong Un had received a personal letter of what was described as “excellent content” from US President Donald Trump.

Talks over North Korea’s nuclear programme broke down after the two men met for a second time in Hanoi in February.

The US wants North Korea to abandon its nuclear weapons entirely before lifting international sanctions, but Pyongyang wants a more staggered approach.

The North Korean Foreign Ministry said it would not “hesitate to pull a muscle-flexing trigger in order to defend ourselves” if anyone dared trample on its sovereignty.

It accused the US of maintaining a hostile approach towards the North, citing recent reports on alleged human trafficking and religious crackdowns.