MTN Nigeria shares rose 10% on Monday to their highest in two weeks after the country’s attorney general withdrew a $2 billion tax demand against the South African telecoms firm.

The company and attorney general both said on Friday that Nigeria’s attorney general had withdrawn the tax case.

Shares in MTN, Nigeria’s second biggest listed firm, rose to 127.60 naira each, helping lift the broader market index by 1.6%.

Nigeria is MTN’s biggest market, with 58 million users in 2018 and it accounts for a third of the South African group’s core profit.

The tax case had cast a cloud over the telecoms firm as investors feared that the demand by the West African nation could affect MTN’s value.

The company floated its shares on the Lagos bourse last year after its parent South Africa’s MTN Group resolved another case with Nigerian authorities over more than 5 million unregistered SIM cards.

Since the $6.5 billion listing last May, MTN stock peaked in September before declining. It fell to 105 naira per share last month, near its listing price of 99 naira.

MTN Nigeria has said it would sell more shares to the public and increase local ownership once the tax row is resolved.