Revenue from electronic road tolls in Gauteng jumped to an eight-month high last month after the government announced stricter measures to ensure payment from motorists. The state-owned Sanral collected about R76-million from the system last month, 25% more than in April, according to data.Collections had peaked at R120-million in June last year, before the provincial government announced a review of the system, causing some road-users to delay payment, Sanral CEO Nazir Alli said in an interview on Wednesday.The rise in toll revenues follows an announcement by Deputy President Cyril Ramaphosa last month that drivers won't be able to renew car registrations unless their e-toll bills were paid, bringing "political certainty" to the project, Alli said at Bloomberg's offices in Johannesburg.The government also cut the maximum amount drivers can be liable to pay per month.Since Ramaphosa's announcement "there's a couple of corporates that came and made lump-sum payments", Sanral chief financial officer Inge Mulder said in the same interview.In addition, the government promised Sanral, which owes R35.5-billion in outstanding bonds and loans, a top-up payment of as much as R700- million. ..