In a meeting with governors general from across Iran, Mahmoud Ahmadinejad said prices should be controlled, particularly food prices, MNA reported.
The president urged governors to investigate using detectives to uncover illicitly inflated prices.
An official from Tehran's Governors office has said a pasteurized milk company has violated rules by inflating the price of milk in Tehran and other cities in the country.
Tehran's Governor General Mortza Tamadon has said that 11 million tons of milk are produced in Iran so there is sufficient demand for prices to be kept steady. However, the managing director of Pak Pasteurized Milk Company retorted that 11 million tons was inaccurate and six million tons was nearer the true figure.
Tamadon also said 13 farmers from Tehran have been fined 150 billion rials (about $1.3 million) for selling milk at high prices.