Spanish banking group Banco Santander has agreed to buy back a 50% stake in its asset management arm from US private equity firms Warburg Pincus and General Atlantic for an undisclosed sum.

The deal will offer Santander 100% ownership in Santander Asset Management, which oversees €170bn in assets.

The US buyout firms acquired the stake in 2013 in a deal that valued the asset management unit at €2.05bn.

In November 2015, Santander signed an agreement to merge its asset management arm with Pioneer, the asset management unit of Italian banking group UniCredit. The merger plans were however, scrapped later due to regulatory issues.  

In addition, Santander, Warburg Pincus and General Atlantic also agreed to explore alternatives for sale of their stake in the Allfunds Bank mutual fund platform.

The options could include a sale or an initial public offering of Allfunds Bank, Santander said in a regulatory filing.

Allfunds is 50% owned by Santander Asset Management. The rest is owned by Italian banking group Intesa Sanpaolom, who separately said that it is considering a sale of its stake in Allfunds.