Talks aimed at settling the mackerel dispute, which has infuriated Scottish fishermen, have resumed.
Skippers from Iceland and the Faroes Islands caused outrage earlier this year by setting their own controversial quotas.
A second round of talks between delegates from the EU, Norway, Iceland and the Faroes are being held in London to try to resolve the row.
Fishing leaders said progress was made in initial talks earlier this month.
Ian Gatt, chief executive of the Scottish Pelagic Fishermen's Association, said: "We are disappointed that a deal was not reached during the first round of talks although we are encouraged that there is the basis for continuing the negotiations into a second round of discussions."
Mackerel is the most valuable stock to the Scottish fishing industry, bringing £135m into the economy last year.
Traditionally Iceland did not land much mackerel but fishermen there argue stocks have moved further north into their waters.
This year the country set its quota at 130,000 tonnes. The Faroe Islands also increased their quota from 25,000 to 85,000 tonnes.
Fishermen from Scotland and Norway claim those quotas threaten future stocks.
Both Iceland and the Faroes have already been warned they could face sanctions over the issue.
The Faroese fishing boat Jupiter was prevented from landing its £400,000 catch at Peterhead in August after being confronted by fishermen angry over the quotas.