Massachusetts is joining Maine to fight a possible ban on North American lobster by the European Union.

All 11 members of the Massachusetts congressional delegation sent a letter Friday to the Obama administration urging it to work with its European counterparts to continue the trans- Atlantic trade of lobsters. The delegation has joined Maine lawmakers to fight concerns raised by Sweden that the American crustacean poses an invasive threat to its own native lobster species.

The Massachusetts delegation voiced its concerns in a letter to Secretary of State John Kerry, U.S. Trade Representative Michael Froman and National Oceanic and Atmospheric Administration Administrator Kathryn Sullivan about the impact of a ban by the EU, which accounts for one-fifth of all American lobster exports.

“A permanent ban on the importation of American lobster to the EU could … have devastating consequences for the Massachusetts lobster industry and the New England maritime economy,” the delegation wrote.

The European Union accounts for one-fifth of all American lobster exports.

The European Union accounts for one-fifth of all American lobster exports. Press Herald File Photo/Carl D. Walsh

The delegation said in the letter that Sweden’s petition to add American lobsters to the European Commission’s list of invasive species is not consistent with its own standards and does not appear to be the correct method to resolve Sweden’s concerns.

“Studies conducted by New England’s leading marine scientists refute Sweden’s assertions that American lobster carry contagious shell diseases and that hybrids of the European and American lobster are viable in the wild,” the letter states.

The letter is the latest salvo in a trade dispute that erupted in March when Sweden announced it was seeking from the 28-country EU a ban on live North American lobsters. Norway, which is not a member of the EU, banned North American lobsters on Jan. 1, saying it shared Swedish concerns. However, trade figures suggest it isn’t being enforced.

The State Department told the Maine congressional delegation in April that it was actively working to ensure that the European Commission does not impede the legitimate trade of live lobsters, including those from Maine. A State Department official told the delegation that the American ambassador to Sweden had already raised the issue with the Swedes.

Sweden claims that North American lobster diseases and parasites threaten European lobsters.

Since 2008, 32 North American lobsters, some with rubber bands on their claws, have been found in Swedish waters. American critics contend the Swedes are overstating the threat to European lobsters, scoffing at the small number of North American lobsters in Swedish waters.

The proposed ban triggered protests by some European chefs who want to continue to serve the larger North American lobster.

Ban opponents, including the Maine Lobster Dealers’ Association, say the proposal has more to do with the market protection for European lobsters than with any environmental threat by American lobsters.

At stake are $10 million worth of lobsters Maine directly exports to the EU annually and much of the $125 million worth shipped from Massachusetts annually, which comes from Maine as well.

Maine lobstermen hauled 121 million pounds of lobster in 2015, worth $510 million, the largest lobster fishery in the nation.

Massachusetts is second, hauling in more than 15 million pounds a year. In 2014, Massachusetts landings generated about $68 million.

Staff Writer Edward D. Murphy contributed to this report.

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