Zambia's largest mobile phone operator MTN has increased the cost of data bundles despite having made several commitments to ensure affordable internet.

The company confirmed the price hike from K148 to K185 for a 2Gb data bundle, and an overall increase of K20 on all other data bundles.

MTN Zambia has not offered any more details on why it decided to implement the new tariffs, and whether or not it was planning to increase the cost of voice communication.

The government described the company's action as "unfortunate".

Deputy Minister of Communications and Transport James Kapyanga said the operator had promised to address the country's low internet penetration through the introduction of affordable data services.

He said while the government does not want to dictate to mobile phone operators how they should price their products and services, operators should be reasonable.

"The increase of course makes sad reading because as a government, our interest is to see the cost of internet coming down for the benefit of the poor citizenry. Therefore the company should live up to its promise of making internet cheaper, especially that it is the biggest operator in the country," Kapyanga said.

He warned that the high cost of internet is likely to slow down internet penetration in the Southern African country.

According to the Zambia Information and Communication Technology Authority (ZICTA), MTN currently has secured 45.5% of Zambia's data market, followed by Airtel with 40.1%.

The country currently has 6.1 million internet users, representing a penetration rate of 39%.