Africa’s richest man, Aliko Dangote, celebrated his 59th birthday commissioning construction of two cement plant worth $1 billion in Nigeria and shrugged off questions raised about his involvement with some four shell companies registered in Panama.

Dangote, who is worth about $17.3 billion according to Forbes rich list, was last week listed in the ongoing Panama papers leak.

While the leak does not say if the shell companies associated with Dangote and his associates were used for illegal dealing, they have raised questions if the tycoon and industrialist has been paying his fair share of tax in Nigeria.

The founder and chairman of Dangote Group, which owns one of Africa’s fast growing cement company, Dangote Cement, spent Friday at a ground-breaking ceremony in Okpella and Itori in Edo State, where his company plans to build two plants with a total capacity of 12 million metric ton per annum.

The plant will increase Dangote Cement’s production capacity to 41 million metric tons annually, Leadership reported.

Devakumar Edwin, The Group Managing Director at  Dangote Cement, said the two plants were expected to come on stream within the next three years.

This he said would help expand the company’s manufacturing plants, thereby reducing the transportation cost component of its operations.

“The new investments will further lower the cost of production, bring about future reduction of the price of cement and also generate employment opportunities for youths of the host communities,” Edwin said.

Dangote, said the new cement plants would further increase the $3 billion Nigeria had been saving from import substitution in cement yearly, This Day reported.

He noted that he would never shy away from investing in the country because the nation still remains the best place to invest in the world.

“A key factor that drives investments in an economy is the presence of an investor-friendly business climate,” Dangote said, adding that developmental challenges facing Nigeria were quite enormous and will require the combined efforts of government and private sector to overcome them.