LONDON (Dow Jones)--Specialist Lloyd's of London insurer Beazley PLC (BEZ.LN) Friday posted a significant rise in first-half pretax profit, boosted by a $33.7 million foreign exchange gain, but said the "intense competition" in many lines of insurance is likely to continue to hit rates. Chief Executive Andrew Horton said the insurer would concentrate on business that remains profitable, adding that Beazley was prepared to reduce its underwriting book where this isn't the case. For the six months to June 30, Beazley posted pretax profit of $115.5 million compared with $30.1 million in the same period a year earlier. The interim dividend increased to 2.4 pence a share from 2.3 pence. Beazley reported gross written premiums of $940.6 million, compared with $894.6 million last year, which was mainly driven by growth in its reinsurance and specialty lines divisions. Overall rates on renewal declined 2% across the portfolio compared with a 5% increase in the first half of 2009. Its investment income totaled $8.5 million, or an annualized return of 0.5%, compared with $40.5 million and 2.9% last year. -By Rachael Gormley, Dow Jones Newswires; 44-20-7842-9308; [email protected] Order free Annual Report for Beazley Group Visit http://djnweurope.ar.wilink.com/?ticker=JE00B64G9089 or call +44 (0)208 391 6028 (END) Dow Jones Newswires July 23, 2010 02:25 ET (06:25 GMT)