Nigeria's President Muhammadu Buhari has said he does not want an apology from UK Prime Minister David Cameron, who described the African nation as "fantastically corrupt". The Nigerian leader, who is on a two-day official visit to the UK to attend an anti-corruption summit in London, called on his counterpart to help repatriate stolen Nigerian assets stashed away in the UK.

"No. I am not going to demand any apology from anybody. What I am demanding is the return of assets. What would I do with an apology. I need something tangible," Buhari said during a press conference on the eve of the summit, scheduled for 12 May.

"By the end of our summit tomorrow, we should be able to agree on rules-based architecture to combat corruption. Corruption does not differentiate between developed and developing countries. It is a serious threat to good governance, peace and security. I call for establishment of an anti-corruption infrastructure that will trace and return stolen assets to their countries of origin," he continued.

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"Unfortunately, repatriating stolen assets is tedious, time-consuming, costly. It entails more than just signing of bilateral agreements. The anti-corruption agencies have been revitalised to tackle the monster. A radical departure from the past. Our administration has zero tolerance for corruption. We have strong reserve to tackle it, even if many feathers would be ruffled."

The Nigerian leader previously said he was "deeply shocked and embarrassed" by Cameron's remarks, suggesting the prime minister could have been referring to Nigeria's previous administrations, marred by corruption.

Buhari's comments came as several Nigerian officials have been accused of corruption and money laundering after he ordered an investigation into arms procurement, amid suspicions millions of dollars had been embezzled by corrupt officials.

The probe also led to the discovery that $2.1bn earmarked to prosecute the fight against Boko Haram terrorists in the country's north-east had gone missing. Meanwhile, information minister Lai Mohammed alleged that Nigerian officials and state employees had misappropriated $6.8bn of public funds during the previous administration between 2006 and 2013.

Buhari vowed he would eradicate corruption after taking office in May 2015. He has sought the help of several countries, including the UK, the US and the United Arab Emirates (UAE), to locate and repatriate embezzled Nigerian funds stashed away outside the African nation.

In an exclusive report by IBTimes UK, members of Security in Africa and Potent Communications warned that Nigerian stolen funds repatriated to the African nation risk being embezzled again, making corruption a vicious circle difficult to break.

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