U.S.-listed shares of BP climbed about 2% on Wednesday after The Wall Street Journal reported Shell was holding early-stage talks to acquire its oil rival. Citing people familiar with the matter, the outlet said BP was “considering the approach carefully” and talks were progressing slowly.

Shares of BP rose Wednesday, lifted by a report that Shell was in talks to acquire it in what would mark a huge deal for the pair of U.K. oil giants.

The Wall Street Journal reported on Wednesday that Shell is holding early-stage talks to acquire bp, citing people familiar with the matter. However, Shell has denied this, and bp has not commented. Talks between company representatives are active, with bp carefully considering the proposal, the newspaper said.