"Smoke 'em if you got 'em," goes the old saying. And in Mexico, Philip Morris International (NYSE:PM) will soon have 'em -- lock, stock, and barrel.

On Monday, PMI announced plans to buy out the 20% stake in its Philip Morris Mexico subsidiary from local partner and Carlos Slim Helu holding Grupo Carso. The purchase price has not yet been set in stone, but the companies say they are circling a target price of perhaps $700 million. This price may be subject to adjustment based on the subsidiary's financial performance over the next five years.

Once closed in September, this transaction will give PMI 100% control over its Mexican subsidiary, with the effect that the company will "marginally" increase its profits in Q4 of this year.

In Mexico, PMI's Marlboro brand is the leading brand of cigarette sold, commanding 53.6% market share in 2012. Other brands owned by the company raise PMI's total share of the Mexican market to 73.5%.