South Africa’s MTN denied it illegally transferred $13.92 billion out of Nigeria, dismissing the allegations as “unfounded and without any merit”.

In a statement, the company “strongly refuted” various media reports, which contained allegations of improper repatriation of money out of the country over a period of 10 years in collusion with a number of commercial banks.

Its response comes after lawmakers in Nigeria’s parliament said they would investigate the claims, reported Reuters.

“The allegations made against MTN are completely unfounded and without any merit,” said MTN CEO Ferdi Moolman.

MTN is of course no stranger to controversy in Nigeria. The allegations come just months after the operator agreed to pay $1.67 billion in fines to the country’s regulator following a row over unregistered SIM cards.

It had originally been hit with a fine of $5.2 billion over the issue, and even threatened to pull out of the country, where it operates as the largest player.