Britain's jobless rate hit a 12-year high in May after a record rise in unemployment over the previous three months, and the figures showed little prospect of any let-up as the economy struggles out of recession. Economists drew scant comfort from the smallest rise in the number of people claiming unemployment benefit for a year, and instead questioned how useful the measure was given employment levels had dived. The Office for National Statistics said ILO unemployment rose by 281,000 in the three months to May, the biggest quarterly increase since records began in 1971, taking the jobless rate to 7.6 percent, the highest since January 1997