The Times reports the stoppage is temporary, with the facility in the Dutch city of Leiden expected to start making the vaccine again after a few months.
It is unclear exactly why the company late last year quietly shut down production, but the Dutch facility has instead turned its attention to making another vaccine for an unrelated virus, The Times reported.
It is also not clear whether the pause has had an impact on vaccine supplies yet.
The drugmaker last month forecasted as much as $3.5 billion in sales of its COVID-19 vaccine in 2022, a 46% jump, having fared poorly compared to rivals.
The company reported sales of $2.39 billion for the COVID shot in 2021, missing its own target of $2.5 billion, in a year marked by manufacturing stumbles, safety concerns and uneven demand for a vaccine once touted as a promising tool for inoculating populations in hard-to-reach areas.
With the Leiden plant temporarily unavailable, it could reduce the supply of the J&J vaccine by a few hundred million doses, the NYT report said, citing one of the people familiar with the decision.
Other facilities have been hired to manufacture the vaccine, but they are either not up and running yet or have not received regulatory approval to make the shot, the report added.
The Hill contributed to this report.