Japanese insurer Mitsui Marine and Fire is poised to launch the largest ever Japanese-backed Lloyd's syndicate as part of aggressive plans to expand into the UK and Europe.

The new operation, Mitsui Marine International, Syndicate 3210, will write property, casualty, professional indemnity and other commercial risks.

Mitsui will start trading from Monday April 3 with an underwriting staff of 16. As yet, Mitsui has refused to reveal how much business it plans to underwrite.

However, active underwriter Allan Guest warned that Mitsui will seek total transparency in its dealings including the removal of overrider payments to brokers.

Mitsui's move to stop paying overriders received the backing of ex-Airmic chairman Richard Reddaway who is group risk manager at GlaxoWellcome.

"I welcome the bold decision of Mitsui not to pay overriders. It moves the debate on to the inefficiencies and duplication within our existing arrangements," he said.