The on-loan striker has scored 16 goals and Albion have agreed a fee of £1.8m should they fail to gain promotion from the Coca-Cola Championship, but the fee will rise by an additional £500,000 if they qualify for the Barclays Premier League next season.
Jeremy Peace, the West Brom chairman, confirming the proposed deal, said: "Roman is making very positive noises and I hope he will be with us next season, whatever division we are in."