UBER's major license problem in Lagos, Nigeria

Uber's booming business in Lagos, Nigeria, has hit a major speed bump.

The local government has begun cracking down on Uber drivers, requiring them to pay huge sums to register for special taxi licenses.

Drivers of the ride-hailing app in Lagos are being told they must pay a minimum of 100,000 naira ($320) per car to the local government for a franchise license.

That's a massive sum when you consider that $320 surpasses the average monthly salary for an office worker in Nigeria. The minimum wage in the country is only about $60 a month.

Annual renewal fees cost at least 30,000 naira ($95) per car.

Any unregistered taxi drivers caught without a license can be fined 50,000 naira ($160).