Wells Fargo said on Wednesday it planned to sell at least $10bn of stock to fund its acquisition of Wachovia, the troubled east coast lender, to create the fourth-largest US bank by assets.

Wells said the offering, which it plans to price after stock markets close on Thursday, could grow above $10bn. Wells previously said it would raise up to $20bn of capital, primarily common equity, to fund the $15bn all-stock acquisition.