The World Bank has banned two African subsidiaries of Oxford University Press (OUP) from doing business with it for three years over alleged corruption.
OUP's Kenyan and Tanzanian subsidiaries made improper payments to government officials, the World Bank said.
UK-based OUP - the world's largest university publisher - said it was disciplining the staff involved.
The World Bank has severed links with several companies in Africa to curb rampant corruption, analysts say.
The alleged corruption involves the supply of school books in Kenya and Tanzania.
The ban against Oxford University Press East Africa Limited (OUPEA) and Oxford University Press Tanzania Limited (OUPT) would stay in force for three years, the World Bank said in a statement.
"The two companies made improper payments to government officials for two contracts to supply text books in relation to two World Bank-financed projects," it said.
OUP had agreed to pay a fine of $500,000 (£318,000) as part of a "negotiated resolution" of the issue, the World Bank added.
"This debarment is testimony to the Bank's continued commitment to protecting the integrity of its projects."
The publisher said it was taking disciplinary action against the employees involved in the "wrongdoing".
"We do not tolerate such behaviour," OUP said.
"We have strengthened our management in the region and are taking appropriate disciplinary action in respect of those involved in this conduct."
The World Bank has banned 83 companies and individuals from doing business with it during this fiscal year as it tries to curb corruption and fraud, it said.
In 2010, it said it imposed a six-year ban on business with Macmillan Publishers Limited because of "bribery linked to an education project in Sudan".