The rupee weakened by 50 paise against the dollar on Monday, as domestic equity markets plunged amid renewed concerns on the US-China trade front. A two per cent fall in the domestic equity markets, a day ahead of key state election results, also hurt the currency market. In a surprise move, Reserve Bank of India Governor Urjit Patel stepped down on Monday, a move expected to spook the Street. While the rupee ended 0.7 per cent lower at at 71.32 against the greenback on Monday, currency forwards indicated a sharp fall in the coming session.