A deal would be a landmark combination of two supermajor oil companies. Shell issued a formal stock exchange denial of takeover talks.

Shell denied that it was in talks to buy BP after the Wall Street Journal reported on Wednesday that the oil major was in early discussions over a takeover of its British rival.

Shell said “no talks are taking place” for a potential megamerger with rival BP that would cost more than $80 billion and represent the biggest energy deal of the century. The denial comes on the heels of the Wall Street Journal reporting June 25 that Shell is in early talks to acquire BP in a much-rumored deal.