Washington: US President Donald Trump has lashed out at China for undermining its work with North Korea, as criticism over progress on denuclearisation on the Korean peninsula mounts. In a series of tweets Trump said he saw no reason to resume the joint war games with South Korea that have angered North Korea, BBC reported.

Days ago Trump’s Defence Secretary Jim Mattis said that military exercises might continue with South Korea. In his tweets Trump accused Beijing of providing North Korea with “considerable aid”, suggesting China was softening the blow of sanctions. “This is not helpful!” Trump said.

China has accused Trump of “shifting blame” on its relations with North Korea. A summit between Trump and North Korean leader Kim Jong-un in June concluded with a pledge from North Korea to work towards “the complete denuclearization of the Korean peninsula”.

But since then many observers say North Korea is not moving fast enough to dismantle its nuclear sites. Days ago, Washington called off a trip to North Korea by US Secretary of State Mike Pompeo with the President arguing that insufficient progress had been made in dismantling the North’s nuclear programme.

Since the June summit, North Korea has halted its missile tests, claimed to have dismantled a nuclear testing site and returned the remains of US soldiers killed in the Korean War. A report by Vox suggests that Pyongyang is reluctant to proceed with denuclearisation because Trump failed to live up to his alleged promise to Kim that he would sign an official declaration to end the Korean War. After a UN report found that North Korea was continuing to work on its nuclear programme, the US urged the international community to maintain sanctions and economic pressure on Pyongyang.