CORRECTED - UPDATE 2-GM offers Opel workers words, not freedom

(In 11th paragraph, please read $8.5 billion, not 8.5 billion euros)

* GM CEO says skeptical of taking Opel brand global

* German chancellor says GM must bear brunt of costs

* Opel bidder Sberbank could take legal action against GM

* Opel labor leader says to negotiate only if funds solid (Rewrites throughout, adding comments from GM CEO)

By Christiaan Hetzner and Sarah Marsh

RUESSELSHEIM/BERLIN, Nov 10 (Reuters) - General Motors Co [GM.UL] dashed hopes on Tuesday that Opel would play a greater role within its vast empire and only offered vague assurances that Detroit would lengthen the leash on its rebellious European carmaker.

Separately, German Chancellor Angela Merkel warned GM not to count on European governments to bear the brunt of the burden to overhaul Opel, after Detroit refused at the last second to hand control over to a Russian-backed consortium built around Canada's Magna International Inc (MGa.TO), triggering an uproar across Germany.

"This solution can only work if GM takes over the lion's share of the restructuring costs, which also means that it has to pay back the bridging loan," she told the lower house of Parliament on Tuesday.