ING Group has bought CitiStreet, a retirement plan and benefit service and administration organisation in the US defined contribution marketplace.

CitiStreet is jointly owned by Citigroup and State Street.

The combined business will make ING the third-largest defined contribution business in the US based on assets under management and assets under administration with €224 billion ($351 billion) in AuM and AuA and the second largest based on plan participants, with more than 14 million plan participants.

The total consideration is €578 million, financed from existing internal resources. It will have no impact on ING's ongoing share buy-back programme.

The transaction also includes a defined benefit/pension business in the US, a health and welfare business in the US and a retirement services business in Australia.

The transaction is expected be closed in the third quarter of 2008.