Oil giant BP has admitted it lobbied the UK government over prisoner transfers with Libya to help its commercial interests there. The lobbying eventually led to the early release of Lockerbie bomber Abdelbaset al-Megrahi.Megrahi is the only person convicted over the December 1988 bombing of a New York-bound Pan Am Boeing 747 over the Scottish town of Lockerbie, which killed 270 people. BP insists it was not involved in negotiations for his release.