Tobacco manufacturing firm Philip Morris International (PMI) said it posted a 6.1 percent jump in its sales volume in the Philippines from January to May.
PMI's total sales volume hit 28 billion units at end-May, nearly 2 billion units more than the 26.4 billion in the same period last year.
Its Marlboro brand led the growth with a 10.3 percent increase while its other brands increased by 5 percent.
PMI Asia region president Matteo Lorenzo Pellegrini noted that the rise in shipment volume occurred amid the "absence of a level playing field."
"Key to this performance has been the marketing support behind our main brands and the significant price investment in order to maintain competitive price gaps to Mighty Corp.'s brands," he said.
Pellegrini, however, said that despite PMI's positive numbers, "there are strong indications based on official tax statistics and Nielsen data that, in 2013, Mighty declared only about half of its sales volume for tax purposes."
He said that while there was a dip in Mighty's estimated sales volume in the first quarter, the proportion of underdeclaration for tax purposes increased during the period.
"This continues to prevent us from being able to operate on a level playing field, impacting both our market share and profitability," he said.
Pellegrini added that the launch of tax stamps in July will help address issues on illicit trade.
"With continuous pressure, we remain optimistic that the Philippines will gradually return to a more stable and fair business environment," said Pellegrini.
"We will continue to encourage the authorities to act decisively and we are hopeful the fiscal tax stamp implementation expected in July will help address this," he added.