TM Lewin, the ubiquitous City of London shirt maker backed by private equity investor Coller Capital, has fallen under the gaze of Japanese trading group Itochu Corporation, according to people familiar with the matter.

Itochu has placed a first-round bid for TM Lewin, according to people familiar with the situation, pitting it against private equity firms and trade buyers in a sale process that could fetch up to £100 million, one of the people said.