UPDATE 1-Beijing Automotive Plans Opel Bid - WSJ

* Bid seen in next few days - WSJ

* Held discussions last week - WSJ

* Opel union leader says GM playing high-stakes game - Bild

* BAIC tells Reuters it has no knowledge of the matter

(Adds BAIC comment, Bild report, bullet points)

July 2 (Reuters) - Beijing Automotive Industry Holding Co plans to present a detailed bid for General Motors Corp's GMGMQ.PK Opel unit in Europe within the next few days, The Wall Street Journal reported, citing a person familiar with the matter.

The Chinese carmaker held discussions with GM last week and is firming up details of an offer, the paper said.

Beijing Automotive currently only makes Mercedes-Benz and Accent cars at joint ventures with Daimler AG (DAIGn.DE) and South Korea's Hyundai Motor (005360.KS).

Speaking in Germany's Bild newspaper on Thursday, Klaus Franz, head of the Opel works council, was quoted as saying that GM was playing a high-stakes game in a bid to improve the terms of the Opel disposal, adding that he knew of no new offer.