The first relief well being drilled to allow the gushing BP well in the Gulf of Mexico to be capped is only 300ft from its target depth, having sunk to a total of about 17,710ft through water and rock, the US authorities said on Wednesday. Bob Dudley, BP’s managing director for the Americas and Asia, who is now leading the company’s response to the spill, told the Wall Street Journal that the relief wells could work between July 20 and July 27 “in a perfect world with no interruptions”, but warned that such an outcome was “unlikely”. Ed Crooks discusses how the latest developments may affect the future of CEO Tony Hayward .