The sterling is sharply lower across the board today, with GBP/USD now losing nearly 1.5% around the mid-1.4100s. GBP/USD much lower on ‘Brexit’ The pair has intensified its decline, reaching 4-week lows in the 1.4150/40 band, following the decision by London’s mayor Boris Johnson to support a campaign to leave the European Union. Comments by B.Johnson have also sent the sterling to the biggest drop since 2010, losing nearly 3 cents since Friday’s tops above the 1.4400 handle. GBP/USD levels to consider As of writing the pair is retreating 1.63% at 1.4167 and a break below 1.4147 (low Jan.29) would expose 1.4100 (psychological level) and then 1.4079 (2016 low Jan.21). On the upside, the next resistance lines up at 1.4400 (20-day sma) followed by 1.4522 (38.2% Fibo of 1.5240-1.4079) and finally 1.4579 (55-day sma). For more information, read our latest forex news.