BUZZ-Admiral rises on firm H1 profit; biggest pct gain on UK's FTSE 100
** Shares of Admiral Group PLC rise ~3.6% at 2106 pence
** British insurer posted a 4% rise to 220 mln pounds ($265.25 mln) in H1 pretax profit, boosted by an increase in customers in its UK business
** Co's profit from UK home insurance business swung to a profit from last year's loss
** Stock top pct gainer on FTSE 100 index
** Shares rise to their highest in more than one week ($1 = 0.8294 pounds) (Reporting by Shanima A in Bengaluru)