BJP boss Amit Shah started work on his mission to reach out to NDA allies, starting from Uddhav Thackeray's Shiv Sena in Mumbai this evening to mollify its oldest and most difficult ally that calls his party its "biggest political enemy". The Shiv Sena, which sees the BJP's efforts to consolidate its foothold in Mumbai and beyond as a threat to its political existence, has promised a divorce ahead of next year's Lok Sabha elections.