Pernod, the world's second largest spirits company, reported a fall in whisky sales in Asia, where it gets 40% of its revenues, for the financial year to the end of June,
This was driven by declines in China, South Korea and Thailand, taking the gloss off strong performances in markets such as Central America.
Pernod has warned since last year that it was finding conditions in Asia difficult. Arch rival Diageo has reported that it too has seen a slowdown in the region.
Overall sales growth at Pernod amounted to 4% taking revenues for the year to a slightly lower than expected €1.2 billion (£1bn).
Mr Lacassagne said: "This year has seen solid growth of our business on a global basis, with a very strong performance by our leading single malt, the Glenlivet, which has contributed more growth to the single malt category than any other brand over the past five years."
Sales of Scotch whisky in Asia declined even as other parts of Pernod's portfolio, such as Martell brandy did well, with overall sales in the region up 7%.
Pernod said that it had been a challenging year for its Scotch brands in China where the whisky market has shrunk and sales of expensive spirits have been hit by a government drive to reduce conspicuous consumption.
Investec analyst Martin Deboo said: "The problem remains Asia, and particularly China, where growth slowed materially in Q4."
The problems come as Pernod continues to increase capacity in anticipation of ongoing rising demand from emerging markets.
It recently re-opened mothballed Glen Keith distillery in Speyside and has plans for a new distillery at Carron, also in Speyside. It is also preparing to officially open a new bottling hall in Paisley where its top-end whiskies are packaged.
Industry trade body the Scotch Whisky Association declined to comment on whether whisky sales in Asia are falling. Its last set of export figures for the 2012 calendar year showed a mixed performance with exports to China up 8% but those to South Korea down 7%.
There were 4.9 million cases of Chivas Regal sold over the year as volumes plateaued. But price increases led to a sales rise of 5%.
Mr Lacassagne, who replaced Christian Porta in July, said "Chivas Regal grew sales on a global basis including strong growth of Chivas Regal 18 [year old] in the ultra premium Scotch segment, strong performances in markets such as Central America, Eastern and Central Europe, and good growth in travel retail following the introduction of a new product, Chivas Brothers Blend."
Ballantine's continued to struggle in the face of economic problems in core markets such as Spain. It posted a 6% sales decline, as volumes and prices fell.
Mr Lacassagne said: "Ballantine's made good progress in emerging markets in South America and Eastern Europe."
Pernod's leading single malt brand Glenlivet did well, recording double digit sales growth in every region as a record one million cases were sold.
Glenlivet had a particularly strong year in the Americas with a 22% rise in sales in the important United States market, thanks to increases in volume and pricing.
Pernod chief executive Pierre Pringuet said: "Despite a less buoyant environment than that of last year, we achieved our guidance."
He added: "Our global and balanced exposure to emerging and mature markets will allow us to seize all opportunities. We therefore remain confident in our ability to pursue our growth."
Mr Lacassagne said: "We will continue to invest strongly in our portfolio, marketing, production and manufacturing facilities to support our growth ambitions for premium Scotch whisky and gin."