Shell has denied it is in talks with rival BP over a possible merger to create a £200billion-plus energy group.
It comes after The Wall Street Journal had reported discussions between the sector giants over Shell potentially acquiring BP.
But now, The Times reports, Shell has insisted that "no talks are taking place".
A Shell spokesman said the Wall Street Journal article was simply "market speculation" and that Shell was concentrating on its own performance.
BP declined to comment.
The Journal report suggested talks were at an early stage but that a merger deal would create a new company worth £209billion.
The Times reports that would make the new firm comparable to American oil majors like Chevron and ExxonMobil in terms of scale.
In the wake of the speculation, New York-listen shares of BP shot up by 10% before settling back to just a 1.8% rise.
The speculation comes as BP sets about implementing a "fundamental reset" in strategy to revive investor confidence, moving away from renewables.