The capacity constraints that have dogged the domestic launch of Japan Tobacco Inc.'s heated-tobacco device will take a while yet to resolve, according to a company executive, handing a further boost to Philip Morris International Inc. in the world's most advanced market for next-generation tobacco products.

Japan Tobacco underestimated the level of demand for its Ploom Tech device since releasing it at home in March, Yasuhiro Nakajima, vice president of emerging products, said in an interview. The cigarette maker is spending tens of billions of yen to relieve the capacity constraints that are preventing it from selling Ploom Tech nationwide.

"We are improving the Ploom Tech supply situation but to be honest it is taking some time," Nakajima said by phone. "I cannot tell you that we can resolve the issue very quickly."