Much of Mr Montague's estimated pounds 30m personal borrowing is with the German bank, understood to be firmly supportive of him.
Martin Kohlhaussen, deputy chairman of Commerzbank, was a director of Tiphook, now Central Transport Rental Group, until he resigned in March 1994, when the bank was preparing to extend significant new lending to the company.
The bank would carry considerable weight in opposing a bankruptcy order against Mr Montague or supporting an orderly repayment of his creditors under an individual voluntary arrangement.
But City sources doubt that Commerzbank will pay off Royal Bank's pounds 2.3m claim. Sources close to Mr Montague hope his financial position will be sorted out within a week from other assets so that the bankruptcy hearing, set for 28 October, will not be needed.
The same sources denied suggestions that he has put his mansion on the market for up to pounds 10m to raise funds.
A spokesman for Tiphook said: 'Mr Montague's personal financial affairs are his own affair. The board is supportive and has been aware of Mr Montague's personal circumstances for some time.'Reuse content