Oil giant may need EGM over TNK-BP sale But the venture is so significant to BP - accounting for 27pc of its proven reserves - that any sale could require shareholder approval. Under Financial Services Authority rules, an oil company disposing of an asset that accounts for more than 25pc of its proven and probable reserves must obtain shareholder approval before completion. BP declined to say what proportion of proven and probable reserves TNK accounted for, but oil analyst Malcolm Graham-Wood, at VSA Capital, said it was likely to be a similar proportion to the share of its proven reserves. One institutional investor in BP told The Sunday Telegraph that, while shareholders were broadly supportive of plans to sell, "that could change if they decide to sell the asset at a price that we don't believe is sensible." A sale for $20bn would be "disappointing," they said, while much below that would see shareholders "up in arms." A BP spokesman said: "For the TNK-BP sale we will of course discuss with the listing authority and comply with the relevant regulatory requirements at the right time to ensure we have the correct approvals, including shareholder approvals if necessary." BP has not held an EGM since 1999, when shareholders approved the $27bn acquisition of Arco. The oil giant has agreed to shed $35bn of assets towards a targeted $38bn to pay for the Gulf of Mexico disaster.