Brent crude reversed early losses to trade back towards $57 a barrel on Tuesday, as a weaker dollar overshadowed signs of slowing growth in China and Saudi Arabian oil production close to an all-time high. Gains were capped by data showing factory activity in China, the world’s second-largest economy and top oil importer, slipped in March. The Chinese data followed comments from OPEC kingpin Saudi Arabia that it is pumping around 10 million barrels of crude per day, close to an all-time high and some 350,000 bpd above the figure it gave OPEC for its February output.