* Argentina’s central bank (BCRA) has allowed the peso to weaken slightly against the US dollar on the official exchange rate, in its first adjustment to the frozen rate since August. The peso is now trading against the dollar at Ar$353/US$1, after being held at Ar$350/US$1 for the past three months. Argentina operates a highly complex array of exchange rates, and only the official, or ‘wholesale’, rate was altered yesterday. This slight devaluation came after Argentina’s secretary of economic policy, Gabriel Rubinstein, said last month that the peso would return to a so-called ‘crawling peg’ from 15 November, which would see it devalue against the dollar by 3% per month.