Newswire report
I don't think this is a surprise given what's going on in the Chinese economy. The risk here is more that the US draws a hard line at a sensitive time.
The report says Chinese officials are hoping the US will agree to some flexibility on pledges, citing people familiar.
The agreement is supposed to take effect in mid-February and has a clause that says the US and China will consult "in the event that a natural disaster or other unforeseeable event" delays either side from complying.