The financial crisis is squeezing the trade credit that oils the wheels of commerce, forcing exporters and importers to pay stratospheric prices for the loans that allow them to ship their goods.
But while anecdotal evidence abounds of ships riding empty outside harbours and goods stuck on the quayside, it is hard to find actual cases of exporters unable to ship their products.
"We're not getting the examples per se of it being stopped. We've got concerns being expressed about the difficulty of obtaining liquidity," said Australian Trade Minister Simon Crean. Mr Crean noted that merchandise trade was by no means the only sector finding it hard to get funds in a crisis that has dried up sources of credit but said the squeeze was undermining efforts to use trade as a stimulus for the world economy.
"The difficulty in obtaining finance for transactions that are committed to acts as a disincentive to the very thing that we're trying to get going and that is the freer flow of trade," he told Reuters. In Chicago, one grain trader said his firm had been readying for the worst but so far the crisis did not appear to have stopped any grain shipments.
"We are loading stuff out and they are paying in a timely manner. (There has been) no hold up on sales because of letters of credit. They talked about it as a possibliity but so far it is not an issue," he said.
But there is anecdotal evidence that trade has been stopped.
"With reports of sellers' banks deciding they don't trust the financial institutions named in buyers' letters of credit, have come alarming anecdotes of cargo ships being stuck in home ports," Matt Robinson, an economist at Moody's Economy.com, said in a report last month.
Around 90 per cent of the $14 trillion in world merchandise trade is funded by trade finance, such as letters of credit - traditional banking instruments dating to the Middle Ages.
Because, in contrast to the sophisticated credit derivatives underlying the crisis, they are simple, short-term and backed by a tangible collateral - the cargo they are funding - they have proven more resilient than other forms of lending.
But the credit crunch, by drying up liquidity, pushed up prices, and already a month ago trade finance deals were being offered at 300 basis points over interbank refinancing rates, three times or more the going rate a year earlier.
"Our problems to obtain financing didn't start in September. Big banks have been reluctant to hand out credits for shipping for one or two years," Alain Solal, president of CAM Cereales, a large French grain exporter to North African countries.
"We have seen all the traditional banks become more fussy, more greedy. They argued that they could make more money elsewhere. We can see where that led," he said.
Mr Solal said banks had been asking for ever tougher and unacceptable terms, while customers were seeking longer payments periods because they were having trouble raising finance from their banks.
He did not cite any deals that had fallen through for lack of trade credit, but expressed concern that measures to revive the banking system would not feed through into trade finance.
The World Trade Organisation (WTO) has called a meeting for Wednesday to discuss the availability and affordability of trade finance.