The airline also informed other American airlines of the threat.
American airlines have been told to increase their inspections of such goods.
That is the largest stake a foreign company can legally own in an American airline.
It is the only smoking ban by a major American airline.
Most other American airlines are expected to follow in short order.
American and other airlines did not return calls for comment yesterday.
The company does not advise employees whether to use American or foreign airlines.
None were sold to an American airline for over three years.
The deal, which is worth £393m, has come under fierce criticism from the other American airlines.
The legendary founder of the first, and greatest, American airline.