US President Donald Trump has signed a new executive order to increase sanctions against North Korea.
Firms and institutions doing business with the North would now be targeted by the US treasury.
Trump said China's Central Bank has ordered other Chinese banks to halt transactions with Pyongyang.
Meanwhile, North Korean leader Kim Jong-un has vowed to make Trump "pay dearly" for his UN speech.
Amid rampant violence against Rohingyas in the Rakhine state, Myanmar's de facto leader Aung San Suu Kyi is under increasing international pressure to act.
In a recent speech, she condemned rights abuses while staying silent on the Burmese Army's role in the alleged ethnic cleansing.
The speech was widely condemned by world leaders and international organizations.
How did the world respond? Here's more.
North Korean Foreign Minister Ri Yong-ho's has called US President Donald Trump's speech to the UN General Assembly "the sound of a barking dog."
During his speech on Tuesday, Trump had threatened to "totally destroy" North Korea if it posed a threat to the US or its allies.
The North has continued its nuclear weapons and missile tests in defiance of the UN.