A meeting on Wednesday between Transport Minister Yiannis Ragousis and taxi drivers, who have been striking since Monday in protest against government plans to liberalize their profession, has failed to resolve the impasse.
The crisis deepened on Wednesday as protesting cabbies scuffled with police in front of the transport ministry headquarters on Mesogeion Avenue, in northern Athens.
Riot police fired volleys of tear gas to push back fuming protesters, who were pelting police with bottles.
Taxi drivers have warned that they will continue with rolling 48-hour strikes unless the Socialist administration revokes its decision to lift all restrictions on the number of taxi licenses issued.
Ragousis said a return to a previous agreement -- signed earlier this year by his socialist predecessor Dimitris Reppas -- is out of the question.
"Following the minister's stubborn stance, all options are open in terms of our protests,? warned Serafeim Kasidiaris, vice president Attica's taxi owners union (SATA).
Speaking on Alter TV, the head of the taxi drivers' union, Nikos Liberopoulos said that two cabbies had died this week ?from the stress and pressure? caused by the uncertainty surrounding their profession.
He also appealed to all taxi drivers to ?respect citizens? and to avoid forms of protest that would lead to confrontation.
The cabbies? action has created frustration for thousands of holidaymakers at the height of the tourist season.