Canada’s largest petroleum producer — Montreal-based Suncor (www.suncor.com) — is to acquire Canadian Oil Sands (COS) for 4.55 billion US dollars (in stocks), ending what it describes as “a three-month stand-off”.

As part of the deal, Suncor agreed to raise its initial bid from 0.25 to 0.28 of its own shares for one COS share. A spokesman said that “this takes into account COS debt, which is valued at 2.4 billion Canadian dollars”.

Suncor launched a hostile bid for COS in October in order to acquire the latter’s only asset — a 36.7% stake in the Syncrude consortium that owns western Canada’s largest oil sands deposit.

Suncor already has a 12% stake in the consortium, which includes six other oil companies (including Exxon Mobil through its Canadian subsidiary Imperial Oil). After initially rejecting Suncor’s first couple of bids, COS called the latest offer “fair” and is recommending it to shareholders.