Partial payments have been allowed since early 2014. Toughened sanctions put in place in early 2012 halved Iran's oil exports and strangled its oil revenue, crippling its economy and finally bringing it to the negotiating table. The sanctions are widely expected to be terminated in 2016 if Iran complies with the terms of the deal agreed on July 14. In the first payment by Indian refiners this week, Essar Oil paid $335 million, followed by $300 million from Mangalore Refinery and Petrochemicals Ltd, $62 million by Indian Oil Corp and $3 million by Hindustan Petroleum Corp. Indian refiners have been depositing 45 percent of their oil payments to Iran in rupees with UCO Bank since 2012. Tehran uses the funds, currently more than 170 billion Indian rupees ($2.6 billion), for importing non-sanctioned goods from New Delhi.