Its research among 1200 company directors conducted in the middle of January found that 16% had already instigated relocation plans or were planning to in connection with Brexit, while a further 13% were actively considering doing so.

More large companies had already moved operations, but small firms were almost twice as likely to be now actively considering the prospect.

Two-thirds of exporters to the EU were looking to relocate overseas, and four in 10 IoD members who are engaged with contingency planning have explored moving operations.

The EU was by far the most commonly-identified destination for firms looking to move or set up operations abroad to deal with Brexit.

Edwin Morgan, interim director general of the Institute of Directors, said: “It brings no pleasure to reveal these worrying signs, but we can no more ignore the real consequences of delay and confusion than business leaders can ignore the hard choices that they face in protecting their companies. Change is a necessary and often positive part of doing business, but the unavoidable disruption and increased trade barriers that no-deal would bring are entirely unproductive.

“We still have a chance to stem the flow, and provide enough certainty to the firms that are considering moving but haven’t yet done so. The UK’s hard-won reputation as a stable, predictable environment for enterprise is being chipped away. Our political leaders must keep this in the front of their minds as we enter this critical phase of negotiations.”