The BJP today said it won't challenge the Shiv Sena for the post of Mumbai's mayor after the two sparring allies produced an inconclusive result in an election for India's richest civic body, Brihanmumbai Municipal Corporation (BMC), which they contested separately last month. The conclusion confirmed an expected patch-up following the months-long bitter campaign ran by two parties against each other and cast doubts over Sena's support to the BJP at centre and in Maharashtra.