NATIONAL WESTMINSTER BANK USA 1ST-QTR NET RISES National Westminster Bank USA said higher loans and core deposit volumes as well as a substantial increase in net interest income contributed to a 16 pct rise in first-quarter earnings to 17.7 mln dlrs from 15.3 mln reported a year earlier. The earnings gain came despite a 1.5 mln dlr reduction of income as a result of placing Brazilian loans on non-accrual. Net interest income totalled 92.5 mln dlrs compared with 91.7 mln dlrs in the same 1986 period as loans, mostly to middle market businesses, increased by 896 mln dlrs. But some of these gains were offset by low levels of interest rates. Provision for loan losses rose to 13.8 mln dlrs from 13.0 mln a year earlier. At March 31, the allowance for loan losses was 114.2 mln dlrs versus 94.8 mln at end of March 1986. Non-accrual loans rose to 286 mln dlrs from 132 mln at the end of the first quarter of 1986, largely because 119 mln dlrs of loans to Brazil were put on non-accrual status. The bank said that if these loans remain on non-accrual for the remainder of the year net income for 1987 would be reduced by about 4.9 mln dlrs. National Westminster Bank USA is a wholly-owned subsidiary of National Westminster Bank PLC.