The three US-based investment funds which own the construction supplies and packaging divisions of the old Quinn Group are set to spend another €10m on the business this year in a bid to support its long-term growth.

The return of Ireland’s one-time richest man to part of his old empire after bankruptcy has attracted dozens of big clients back to do business, his colleagues have said.

A director at Anglo Irish Bank was left “speechless” after a representative from the financial regulator suggested the bank consider releasing the Quinn Group from a €250m guarantee.