Peter Rees QC has stepped down as legal director of Shell, just three years after joining the company from Debevoise & Plimpton.

The oil giant said a replacement had not yet been identified, but that Rees would remain in the post until 11 February in order to "assist with the transition of his responsibilities".

In a statement, a spokesperson added: "Shell can confirm that Peter Rees is stepping down as Legal Director of the Company with effect from 10 January 2014 to pursue other interests."

Shell also thanked Rees (pictured) for his service to the company, which he joined in November 2010 from the London office of Debevoise, a year after taking silk.

As legal director, Rees sat on the executive committee of the company, and oversaw a 17% reduction in the size of the legal team to 1,000 staff, of which some 700 are lawyers or intellectual property professionals.

Earlier this year, Rees headed a comprehensive overview of Shell's global legal advisers, which saw a host of UK and US firms appointed to advise the world's largest company by revenue.

Speaking to Legal Week at the time, Rees said: "We will no longer have a global panel of firms that will act for us. Globally it will be much more a series of relationships with firms that have capabilities in the jurisdictions we are working in."

More than 150 local firms were appointed to advise on specific practice or regional matters, while 11 firms – including Norton Rose Fulbright, Debevoise, Allen & Overy and Baker & McKenzie – are set to advise the company in three jurisdictions or more.

Rees started his legal career in 1979 at Norton Rose, later going on to head the firm's dispute resolution practice in 1987 and joining the executive committee in 1997.

In an interview in 2011, Rees called his seat on Shell's executive committee "a huge selling point – I have spent my life advising businesses but you never get access on the commercial side".