MUMBAI, Dec 4: Pivotals suffered a setback on the Bombay Stock Exchange (BSE) today on emergence of selling pressure after news that president K R Narayanan had dissolve parliament. The session commenced subdued but a several pivotals rallied during the mid-session. However, increased selling pressure at the higher level,share turned weak.The BSE sensitive index opened on a weak note at 3530.31, touched the day's high of 3595.00, finished at 3527.10,with a net loss of 35.27 points. The BSE-100 index lost by 15.15 points to 1528.71 as against the previous close of 1543.86.Brokers said that sentiment was slightly better during the mid-session on short covering but turned weak soon after the decision by president to dissolve the Lok Sabha. Now the market will take a new directions in view of announcements of election dates and future trend would depend on the political stability at the centre.Domestic and foreign funds might stay on sidelines in the coming days. FIs today, however,made good purchases in key shares like SBI, Telco, Larsen, Tisco, VSNL, and others. Reliance and ITC remained better in the weak market in view of short covering.On the National Stock Exchange (NSE) pivotals declined moderately following speculative selling pressure from operators.The NSE-50 index opened at 1030.20 and ended at 1011.75, netting a loss of 18.95 points over the previous close of 1030.70.The Midcap index lost by 21.40 points to 1146.50 as against the previous close of 1167.90 The total turnover amounted to Rs 2098.89 crore.