International mobile service companies are flocking to Africa for a slice of the world’s last unsaturated mobile market, but critics say their services are poor.

Mobile service providers provide poor quality services, exploiting paying customers, according to a survey by the Communications Authority of Zambia (CAZ).

The companies surveyed in January and February this year include Celtel Zambia and MTN, according to CAZ CEO Shuller Habeenzu.

The companies failed to meet the minimum service level, as measured by CAZ, for a call-success rate of 95 percent, Habeenzu said, speaking at a press conference on Wednesday in Lusaka.

Celtel is a unit of Kuwait cell phone operator MTC Tele.kw, which operates in 14 African countries including Malawi, Nigeria, Kenya and Democratic Republic of Congo (DRC). MTN operates in 21 countries including Uganda, Zambia, Nigeria and Ghana.

Habeenzu said CAZ is working with the Zambian Ministry of Communications and Transport to come up with legislation that would empower the communications authority to impose stringent penalties on mobile companies offering poor services.

In Zambia the penalty for offering poor services to customers by a mobile service company is US$250. But Habeenzu said the new law will require greater compensation from service providers.

"The amount service providers are currently paying as compensation is little compared to the revenues the operators collect and the damages caused to customers by the poor services. CAZ is proposing an increase on the penalty," Habeenzu said.

Poor service provision by mobile service operators has become a source of concern in many countries in Africa.

In Nigeria last month, the Nigerian Communications Commission (NCC) directed both MTN and Celtel to pay a total amount of about US$40 million as compensation to subscribers as a result of congestion on their networks in December 2007.

MTN and Celtel then filed a lawsuit to halt the directive, but the federal high court in Lagos ruled that they had to offer compensation, as directed by NCC. There have also been similar complaints from Celtel subscribers in Malawi.

In March this year, MTN CEO Phuthuma Nhleko said his company plans to invest about US$4 billion in upgrading its infrastructure in Africa this year, in order to alleviate network congestion and increase subscribers.