Chaucer made the move earlier this month after its retained agency, Haggie Financial, was forced to drop the account because of its work for Amlin.
Amlin, which has retained Haggie Financial since its creation in 1998, confirmed it was in talks with Chaucer last week.
The company is pushing for a recommended offer which it hopes will pave the way for the creation of one of the biggest insurers in the Lloyd's market.
Market watchers have speculated that a successful Amlin-Chaucer deal could set off a round of consolidation in the Lloyd's market, swallowing up many of the smaller listed companies.
But the appointment of FD suggests that the target firm's board is not yet ready to rubber stamp the deal. After last week's announcement, Chaucer was valued at £177m.