Slaughter and May, Cleary Gottlieb Steen & Hamilton and Uria Menendez have won roles as Banco Santander buys back a 50% stake in its asset management unit from US buyout houses Warburg Pincus and General Atlantic.

The deal will give Santander full control of its asset management division, which has €170bn (£145bn) of assets under management and generates €1.1bn (£938m) of fee income.

Cleary is advising Warburg Pincus and General Atlantic with a team led by London finance partner Simon Jay, tax partner Richard Sultman and finance partner Carlo de Vito Piscicelli, who splits his time between London and Milan.

Slaughters and its Spanish best friend firm Uria are acting for Banco Santander. Slaughters' team is being led by City corporate partner Michael Corbett, while the Uria team includes Barcelona managing partner and M&A partner Antonio Herrera, and Madrid corporate partner Stephen Hess.

The pair previously won a mandate to advise Santander in April last year on a deal that saw it attempt to combine its asset management business with UniCredit's Pioneer Investments. That deal ultimately collapsed in July this year, shortly after Jean Pierre Mustier took over as chief executive of UniCredit.

UniCredit Pioneer Investments had instructed Linklaters. Davis Polk & Wardwell also acted alongside Slaughters on the deal.