Olswang has formed an alliance with US law firm Cooley, with the pair set to boost referrals going forward.

Olswang has agreed a non-exclusive alliance with the West Coast tech leader, following discussions between Olswang chief executive David Stewart and senior partner Mark Devereux and Cooley chief executive Joe Conroy and chairman Stephen Neal, which kicked off six months ago.

The relationship will give Olswang new links into the US market after its formal relationship with Greenberg Traurig, formed in 2005, wound down following Greenberg's launch in London last June.

The firms last week began introducing partners across sector and service lines but issues such as secondments and potential joint training initiatives are still to be decided.

Cooley, which has been one of three US allies to SJ Berwin alongside Paul Weiss Rifkind Wharton & Garrison and Goodwin Procter, ranked 56th in the latest Am Law 100, reporting a revenue drop of 8.2% to $507m (£342m) while profits per equity partner fell by 11.4% to $1.17m (£788,000).

The Palo Alto-based firm has 10 offices across the US, including a sizeable New York practice.

Olswang's Stewart said: "We have significant sector overlap and strong service line synergies. Both firms are keen to pursue this relationship given the increasing globalisation of the business of our respective clients, and the increasing importance of technology and intellectual property to global businesses of all types."

A Cooley spokesperson said: "Cooley is pleased to have established a relationship with Olswang, which is based on our complimentary practices and our shared commitment to serving the needs of innovative and growing businesses in an increasingly global economy."

The news comes as SJ Berwin's merger discussions with Proskauer Rose move to a more advanced stage with partners in individual practice groups now travelling overseas to discuss synergies. However, the firms have not yet set a date for a vote on whether to agree a merger.

Additional reporting by Sofia Lind.