A consortium wanting to take over Edinburgh-based Forth Ports has withdrawn its proposed offer blaming "economic uncertainty".
The group Northstream, which included the company that owns Clydeport, had hoped to buy Forth's seven facilities including Leith, Grangemouth, Rosyth, Dundee, Methil, Burntisland and the giant Tilbury docks near London.
But its £640m valuation fell short of that placed on Forth Ports PLC by its directors.
BBC Scotland understands that Forth Ports refused to open its books to show the value of its assets, and the consortium was left with no choice but to withdraw, without making a formal bid.
However, Northstream's members still control more than a quarter of Forth Ports shares.
It is believed they will watch to see whether the current management can achieve the higher share value which they have said can be reached.
In all the consortium made three offers - its first valuation was £12.85 per share; then £13.40 per share and finally £14 per share.
On Thursday, Forth Ports was trading at £12.75.
The consortium is made up of Peel Holdings, which owns Clydeport's facilities at Hunterston, Greenock and Ardrossan, as well as the Port of Liverpool, the Medway Ports in Kent and the Manchester Ship Canal.
Its partners were two infrastructure investment companies; Arcus, which had the largest part of the Northstream holdings, and RREEF, an infrastructure company owned by Deutsche Bank.
In a statement to the London Stock Exchange on Thursday evening, the Northstream consortium said: "In light of the current economic uncertainty and the resultant difficulty of valuing Forth Ports' property assets from public information, the consortium is unable to justify increasing its proposed offer further.
"As a result, and after careful consideration, the consortium has decided not to proceed with an offer for Forth Ports".
The uncertainty over Forth Ports' assets has focussed on the potential for 400 acres of land it owns on Edinburgh's foreshore.
Some of it has been developed, but much of it lost considerable value following the credit crunch, and awaits an upturn in the market.
A spokesman for Forth Ports commented: "Clearly, the consortium were not able to match our shareholders' expectations.
"Forth Ports has set out very clearly it's opportunities for growth, and shareholders support that strategy. The management will now get on with building the business for the benefit of all its stakeholders."