By Lars Mucklejohn The head of Revolut’s business-to-business offering has said it is “aggressively doubling down” on the business market, after the unit’s global revenues exceeded $500m (£380m) this summer. The London-based fintech said monthly transaction volumes at Revolut Business have reached $17bn (£13bn). The unit now makes up between 15 and 25 per cent of the wider group’s revenues. Revolut Business launched in 2017 and provides an automated financial platform for businesses, including start-ups and large corporates. More than 250,000 businesses are said to use the offering each month …