london july 20 reuters  a key british mortgage rate fell on thursday for the first time in nearly two months coming off the previous days 15year high as concerns about the outlook for inflation and bank of england interest rates eased the average twoyear fixed residential mortgage rate  the most common form of home finance  fell to 679 its first drop since may 27 from 681 on wednesday figures from financial data provider moneyfacts showed last month the boe raised its key interest rate to 5 from 45 following fasterthanexpected inflation and wage growth and investors subsequently bet that the boe might raise rates as high as 65 those concerns in turn pushed twoyear fixedrate mortgages above the peak they hit last october when then prime minister liz truss budget plans caused turmoil in britains bond market the rise in borrowing costs has weakened the countrys housing market adding to drags on the broader economy however a lowerthanexpected consumer price inflation reading on wednesday caused boe rate rise expectations to weaken and pushed down twoyear swap rates which underpin mortgage borrowing costs investors now think the chance of 575 or 6 peak in the boes bank rate is split evenly the average interest rate for a mortgage with a fiveyear fixedrate period also fell on thursday edging down to 631 from 633 on wednesday moneyfacts said