By Jarrett Renshaw and Steve Holland WASHINGTON (Reuters) – U.S. President Joe Biden will announce a plan on Wednesday to sell off the last portion of his release from the nation’s emergency oil reserve by year’s end and detail a strategy to refill the stockpile when prices drop, administration officials said. The plan is intended to add enough supply to prevent oil price spikes that could hurt consumers and businesses, while also assuring U.S. drillers that the government will swoop into the market as a buyer if prices plunge too low. Biden’s efforts to use federal powers to balance the U.S. …