Brazilian steel firm Companhia Siderurgica Nacional wants to make a rival bid for Corus before the Anglo-Dutch group's shareholders meet on December 4 to consider an offer from India's Tata Steel, a report said.
CSN announced on November 11 that it had made an informal bid approach to Corus, setting the stage for a bidding war and throwing Tata Steel's agreed takeover into jeopardy.
CSN's offer of 475 pence per share for Corus, which would value the firm at $5.3 billion pounds, including debt, topped Tata's bid of 455 pence.
Benjamin Steinbruch, CSN's chairman, chief executive and 45 per cent owner of CSN, told Financial Times that Corus was being "fair and professional" as a special team from the Brazilian firm met in London to study its accounts.
"We are confident that we will be able to move to a formal bid," Steinbruch was quoted as saying.
"Depending on the quality of the information, discussions will be finalised at the end of this week. We would like to be prepared before the Corus EGM," he said.
The extraordinary general meeting with shareholders is set for December 4.