Norton Rose is to focus its Spanish referrals on national giant Garrigues, it has emerged, as the two firms concede they have been building their informal links.

The top 10 London firm has confirmed it is now focusing its referrals in Spain on Garrigues, amid mounting claims from local rivals that the two firms are positioning themselves for a tie-up.

The top 10 City firm has admitted the firm is operating a referral relationship with Garrigues and partners at the UK firm have told Legal Week the Spanish outfit has become its usual referral firm in Spain. But both firms have insisted the relationship is not exclusive or formal.

Despite denying a formal link-up, one Norton Rose partner commented: "I do not sit here and say: 'which firm should I go to in Spain?' I go to Garrigues."

A Norton Rose spokesman stressed that the firm also worked with other Spanish firms. Commenting on Garrigues, he added: "We have a good but non-exclusive relationship."

Norton Rose, one of the few top UK firms not to have a local Spanish office, publicly tied up with Garrigues in 2003 on a successful joint pitch for Nestle's European M&A and finance and capital markets work.

In addition, Garrigues' managing partner Jose Maria Alonso, spoke at Norton Rose's partnership conference last autumn.

Since 2003 it is understood that the firms have worked together on a number of joint pitches and training sessions, as well as a number of carbon neutral projects.

Alonso told Legal Week: "We have a relationship with Norton Rose, as we have with other UK firms. We have shared some clients with them, but that is it."

Meanwhile, Herbert Smith is waiting on Spanish referral firm Cuatrecasas' decision on whether to join the UK firm's alliance network with Germany's Gleiss Lutz and Dutch firm Stibbe.

Partners at Cuatrecasas have said the management is in a period of "deep reflection" over the firm's international strategy, which will be discussed by the partnership at a conference at the end of the year.

Additional reporting by Claire Ruckin.