(LEAD) No. 2 U.S. diplomat in Beijing for talks on N. Korea sanctions

(ATTN: ADDS quotes, details in last 6 paras; RECASTS lead para) BEIJING, Jan. 21 (Yonhap) -- U.S. Deputy Secretary of State Antony Blinken held talks with senior Chinese officials on Thursday as Washington pressed Beijing to join in drawing up toughe