US president Donald Trump said Russia insists it has the situation under control, but added that not much information was coming out. (EPA Images pic)

WASHINGTON: US President Donald Trump said Wednesday that the death of a Russian plague laboratory worker did not appear to be linked to a biological weapon.

"We don't think so. We're going to find out soon enough, but we don't think so," Trump told reporters in the Oval Office when asked if a "bio-weapon" was involved.

Russia warned earlier against "false" information as reports emerged of a second suspected case. The US and UN have urged Russia to be more transparent.

Trump said Russia insisted it had the situation under control, but added that not much information was coming out.