U.S. President Donald Trump signed an executive order on Monday that aims to reduce the time it takes to approve pharmaceutical plants in the country, as part of new regulations to encourage domestic manufacturing.

Trump ordered restrictions on gain-of-function research, which involves experimenting with viruses and has the potential to cause pandemics.

The executive order adds on to Trump’s planned tariffs on pharmaceuticals in his overall strategy to onshore production of medicines. At the White House event, Trump told reporters that he will announce pharmaceutical-specific tariffs in the next two weeks.