Brysam Global Partners, a US private equity firm set up by two senior Citigroup executives, has announced its first investment taking a $230m (€173m) stake in a Mexican financial services group.

Robert Willumstad, former president and chief operating officer of Citi, and Marge Magner, former chairman and chief executive of Citi's global consumer group, formed Brysam at the beginning of year and have raised a $1bn fund.