Abuja - Nigeria has promised to protect and hand out hefty rewards to whistleblowers, as Africa's most populous country battles both endemic corruption and a sharp decline in oil revenues.Whistleblowers could be entitled to between 2.5 and 5% of funds recovered from information they provide about corruption, Finance Minister Kemi Adeosun told reporters in Abuja late Wednesday.Adeosun said the policy was aimed at boosting awareness of financially related crime and improving public confidence in public institutions. Any funds recovered would be used to finance Nigeria's infrastructure deficits, as the cash-strapped nation battles with falling oil prices, which account for 70 percent of government revenue.The minister said whistleblowers would have their anonymity and protection from prosecution guaranteed, as well as compensation in the event of intimidation or victimisation. President Muhammadu Buhari was voted into power last year vowing to stamp out endemic graft in the West African nation. Buhari has repeatedly accused the government of ex-president Goodluck Jonathan of a "mind-boggling" looting of the treasury. Dozens of prominent members of the Jonathan regime, including ministers, politicians and relatives, have been charged with graft.Several senior judges face charges of fraud, bribery and money laundering. But critics have claimed that Buhari's anti-corruption crusade comes at the expense of the economy, which is in the throes of a recession due to lower crude prices and renewed militant attacks in the oil-producing south.