Beijing said on Friday it will look into charges against two Chinese firms sanctioned by the US because they are suspected of helping North Korea evade sanctions. China upholds all UN Security Council sanctions against Pyongyang over its nuclear and missile programs, Foreign Ministry spokesman Geng Shuang said. He said China will deal with any verified transgressors and “launch an investigation according to our domestic laws,” AP reports. Geng added, however, that Beijing opposes unilateral sanctions on Chinese firms such as those imposed by the US separate from those of the UN.