NAHCO’s spokesman Mr Tayo Ajakaiye said the Vice Chairman, Mr. Denis Hasdenteufel, would act as chairman.
Hasdenteufel will preside over board meetings pending approval of regulators and further announcements from stakeholders.
Yahyah, appointed a director of the company in November 2006, became chairman in July 2012.
According to Ajakaiye, Yahaya, in recent months, came under pressure from his family to step down to enable him undergo treatment.
Yahaya is credited with reorganisng NAHCO to its modern status.
He has been battling an undisclosed ailment for years.
Yahaya said: “During his tenure, the company’s turnover grew from 6.92 billion to 8.5 billion in 2015. This is besides increase in employees from 1,100 to 1,980…’’
” During this period, the asset base also grew from 9Billion to 15Billion.
The hallmark of Yahyah’s tenure at NAHCO was the modernization of Company’s equipment to align with world’s standards in modern ground handling service. He was credited with equipping NAHCO with state-of-the-art equipment that made the Company the great force that it is today in groundhandling service in sub-sahara Africa.
“The diversification of the Company which the board under his tenure embarked upon led to the establishment of NAHCO FTZ with the granting of a licence for same by the Federal Government. The Mainland Cargo Options also joined the growing list of companies in the group.
“Yahyah also promoted a harmonious Company – labour relations which ensure minimal disruption in company’s business operations.