Buhari said this during ajoint briefing with South Africa President Cyril Ramaphosa in Abuja on Wednesday.
He was speaking on the Continental Free Trade Agreement (CFTA) which Nigeria is yet to become a signatory to.
He said he is still studying the agreement and will soon sign it.
The president said: “I am very careful about what I sign whether it is my cheque book or agreements especially when it involves nations and states. As your president has said, we are so populated and have so many young unemployed citizens and our industries are just coming up.
“So, in trying to guarantee employment, goods and services in our country, we have to be careful with agreements that will compete maybe successfully against our upcoming industries.
“I was presented with the document; I am a very slow reader maybe, because I am an ex- soldier. I didn’t read it fast enough before my officials saw that it was all right for signature. I kept it on my table. I will soon sign it.”
The CFTA is an agreement which 44 African countries to form a $2.5 trillion continental free-trade zone,
The free-trade zone is the largest in the world since the creation of the World Trade Organisation in 1995
The CFTA is expected to “create a single continental market for goods and services, with free movement of business persons and investments”.
The agreement is also expected to boost the level of intra-Africa trade from the current 14 percent to over 52 percent by 2022.
Nigeria was s when the 44 countries signed the agreement.
Following criticisms that trailed this, Buhari had explained: “We are widening and deepening domestic consultations on the CFTA, to ensure that all concerns are respectfully addressed.
“Any African Free trade agreement must Fairly and Equitably represent the interest of Nigeria, and indeed, her African brothers and sisters.”