Greek islands faced food and fuel shortages for a sixth day on Tuesday as striking seamen said they would extend their action for at least another 48-hours, until the end of the week.
The seamen, protesting the government's economic austerity programme, decided to continue the rolling 48-hour strikes following a meeting of their union.
Their protest has already affected hundreds of Greek islands, many of which rely on the mainland for supplies.
Dock workers are demanding a collective wage agreement and an end to undocumented and uninsured employees.
The workers also want the government to cancel a plan to regulate the minimum number of dock workers required in each crew, saying that this would lead to layoffs.
Speaking on private television channel Mega, Merchant Marine Minister Costis Mousourlis said that the government had made an offer to dock workers with terms to end their strike, including the settlement of arrears from shipowners.
"There is no reason for the strike to continue," he said.
The government is examining the possibility of issuing a new civil mobilization order to force the seamen to return to work.
The measure was used by the government in January to make Athens Metro workers return to work after a nine-day strike that caused traffic chaos in the Greek capital.
Greek unions have held dozens of strikes over the past three years to protest the harsh austerity measures the government has passed to secure vital bailout loans from the European Union, the European Central Bank and the International Monetary Fund.