It took over Poundland in a £610 million deal in September a year ago.
Chief executive officer Marcus Jooste resigned with immediate effect on Wednesday after the global furniture and clothing retailer reported irregularities in its accounts that require further investigation.
The South African company has also postponed its full-year results, which were meant to be released today.
Shares in South Africa-based German retail giant Steinhoff - which owns Ackermans, Pep, and Russels - fell nearly 60 percent on Wednesday after the company announced the resignation of its CEO in the wake of alleged accounting irregularities.
Steinhoff said in a statement that it would publish its audited 2017 consolidated financial statements when it is in a position to do so.
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Steinhoff also said that it was advising its shareholders and other investors to exercise caution when dealing in the securities of the company.
It bought Poundland a year ago and has introduced its Pep&Co budget clothing brand into scores of stores.
The group, which owns more than 40 local brands in over 30 countries, said it has approached PWC to carry out an independent investigation after new information came to light related to accounting irregularities.
Ben la Grange, chief executive of Steinhoff African Retail, which owns South Africa's...
It had previously rejected allegations made in a Manager-Magazin report that Jooste is among employees being investigated by German prosecutors in a 2015 case linked to possible accounting fraud.
It is not clear if these are the accounting irregularities Steinhoff is referring to in its latest statement.