JOHANNESBURG (Reuters) - South Africa’s Finance Minister Malusi Gigaba on Tuesday denied unlawfully granting citizenship to five members of the wealthy Gupta family, who are friends of President Jacob Zuma, during his time as minister of home affairs.

South Africa's Finance Minister Malusi Gigaba speaks with journalists at the World Economic Forum on Africa 2017 meeting in Durban, South Africa, May 5, 2017. REUTERS/Rogan Ward

New allegations in recent weeks of inappropriate collusion between state-owned companies and business interests close to Zuma have put more pressure on the scandal-plagued leader and ministers close to him.

Gigaba has come under fire after Julius Malema, leader of the opposition Economic Freedom Fighters (EFF) party, tweeted pictures of government documents showing Gigaba had fast-tracked the naturalization process for Gupta family members.

In a statement, Gigaba confirmed the authenticity of the documents but denied they showed he had acted unlawfully.

“I have requested the Department of Home Affairs to provide chronological details of how all applications by the Gupta family have been handled by the Department of Home Affairs from the beginning,” Gigaba said. “We have no doubt that the whole process has been handled by the book in terms of our laws.”

He said it had been within his powers as home affairs minister to shorten the citizenship process and that such courtesies had been extended to business executives and sports people as well as the Gupta family members.

Gigaba was appointed as finance minister in March, replacing Pravin Gordhan, a favorite of international investors, who was sacked by Zuma. The cabinet reshuffle prompted ratings agencies to downgrade Africa’s most industrialized economy, citing heightened political risk.

Gary van Staden, a political analyst at NKC Independent Economists said the allegations against Gigaba risked further undermining investors’ confidence in South Africa, although they were unlikely to immediately impact investments.

South Africa depends on foreign investment to finance its big budget and balance of payments deficits.

The EFF last week filed a criminal complaint against Gigaba over what it says is evidence of corruption in a lucrative government tender. Gigaba and the Gupta family have denied doing any wrongdoing.

Malema is the leader of the ultra-left EFF party which emerged as electoral kingmaker in Johannesburg and the capital Pretoria at municipal elections in August last year. A former protege of Zuma, he was expelled from the ruling African National Congress in 2011 for bringing the movement into disrepute.