President Goodluck Jonathan said yesterday in Abuja that Nigeria had made significant progress in addressing its security challenges.

Jonathan spoke after the new Ambassador of Switzerland to Nigeria, Mr Hans-Rudolf Hodel, presented his Letter of Credence at the State House.

"We are making significant progress in meeting our recent security challenges and we shall continue to improve; so investors have nothing to fear," he said.

The News Agency of Nigeria (NAN) reports that the president also received three other new ambassadors: Mr Svante Kilander of Sweden, Dr Joachim Oppinger of Austria and Mr. Ashraf Salama of Egypt. He urged them to encourage more business delegations from their countries to visit Nigeria.

"Nigeria is a huge market with many green areas waiting for investors. I urge you to prepare the ground for more robust economic relations between our two countries," he said.

Specifically, Jonathan told Salama that Nigeria and Egypt had a crucial role to play in the African Union.

Responding, the ambassadors told the president they were impressed by the vast opportunities in Nigeria.

They also expressed the determination to improve trade and other mutually beneficial relations with Nigeria.