Simmons & Simmons is holding its Tokyo office head, Rika Beppu, to her full notice period in order to retain its joint venture with Japanese law firm TMI Associates.

The delay means that Beppu will be unable to join Lovells until late October - six months after she - and fellow partner Philip Hyde - handed in their notice to join the rival City firm. Hyde was released from the Simmons partnership at the end of July.

Beppu is the registered joint venture partner for Simmons in Tokyo and regulatory requirements mean the firm needs to have at least one registered partner in the office in order to retain its joint venture in the country. London corporate partner Jason Daniel is relocating to the office but is still waiting for his registration to be finalised.

The departure of the two partners led to Simmons laying off four associates and one paralegal at its Tokyo arm. The departures leave the office with just one associate and a trainee, in addition to Daniel, outside the TMI lawyers. Simmons has stressed it is still committed to the much-touted Tokyo legal market as well as its joint venture.

Simmons senior partner David Dickinson told Legal Week: "These things take time. As soon as Daniel is registered as our joint venture partner, Rika Beppu can leave."