Nomura has been in early stage talks to buy Collins Stewart, the UK corporate finance and broking business, just months after the Japanese bank scaled back its US operation after losing more than $600m (€423m) on investments in sub-prime mortgages.

A source close to the situation said the two have been in discussions. Shares in Collins Stewart rose slightly this morning, valuing the business at over £440m (€616m) on the expectation the company could confirm today that it has been in preliminary talks with a potential buyer.