After earlier reports that AstraZeneca and New Jersey-based competitor Bristol Myers Squibb were exploring a mega merger, sources told Reuters the pharmaceutical giants will not consider a potential deal.

Citing two anonymous sources, Reuters reported Aug. 5 that talks are not currently active between the U.K. drugmaker and BMS.

One of them added that, “There was never a deal to be done and there no discussions between the companies,” according to the news outlet. Given the size of the potential ⁠deal, the source noted Britain’s ​market abuse rules would have required ​an announcement if negotiations were underway.

Media representatives from AstraZeneca and Bristol Myers Squibb did not immediately respond to a request for comment on the latest.

The development comes days after the Financial Times reported the parties were considering a tie-up that would create an entity worth roughly $400 billion. The report did not describe the structure of a potential transaction. However, it said the companies had held early-stage talks in recent months about combining.

Besides being one of the largest deals ever in the pharmaceutical industry, the transaction would have established one of the largest mergers in corporate history. A deal would unite Bristol Myers Squibb’s strengths in immunology, hematology and neuroscience with AstraZeneca’s cancer portfolio and global reach.

As of July 31, Lawrenceville-headquartered BMS was valued at $133 billion and U.K.-based AstraZeneca at $264 billion.

News of the unconfirmed deal talks had drawn questions from analysts on whether it would create enough strategic value. Concerns also focused on regulatory scrutiny and disruptions to R&D timelines during integration, according to Fierce Pharma.

Following the Financial Times report, AstraZeneca’s stock slid nearly 9%. The company’s London-based listed shares rebounded about 3% after Reuters reported that no discussions were underway. BMS shares were little changed.