In a letter to European Commission Vice President Valdis Dombrowskis, Tajani said the new health warning labels "risk being a source of distortion of international trade, equivalent to a quantitative restriction".
He said the Irish move, as well as being open to criticism under EU law, "could trigger a chain reaction that would end up damaging the whole of the Union".
Italy has said it will appeal to the World Trade Organization against the warnings on wine, beer and spirits highlighting risks of liver damage and links to certain forms of cancer.
Italian officials have stressed that wine is good for you when drunk in moderation and Italy has said it will make common cause with other big wine producers like France and Spain.
Ireland earlier on Friday notified the WTO of its new labelling policy.
It is hoping to bring in health warnings on alcoholic drinks, including wine bottles, similar to those on cigarette packets within two or three months after getting the all-clear from the European Commission for its controversial plan, an Irish government official has said.
Italy and other wine-making countries such as France and Spain are staunchly opposed to the labels.
Claire Gordon, manager of the tobacco and alcohol control unit at the Irish Department of Health, told Euractiv that Dublin was "very grateful and indeed somewhat surprised" that the EU had given the green light to the plan.
"Clearly what we're doing is a breach of the single market in some way, in the sense that we're looking for extra changes to a product compared to the way it's sold in other countries," she said.
"Hopefully within two to three months, we'll be able to kick off this law and then the next thing is for everybody else to follow".
ANSA
