WASHINGTON  — US President Donald Trump said yesterday he would speak very soon with Russian President Vladimir Putin over the reported plague death of a laboratory technician, as Washington and the United Nations called for transparency from Moscow.

Russian authorities denied that they were imposing anti-plague measures and played down the reports of an incident at a plague research institute in Siberia’s Irkutsk region last week.

But Washington is showing growing concern, with Secretary of State Marco Rubio calling on Russia to be open about the situation. The World Health Organisation issued a similar appeal yesterday.

“We encourage Russia to be transparent and share more information with the world so that all of us could react accordingly and appropriately,” Rubio said during a trip to Iceland.

Trump later said he would be speaking to Putin about what happened.

“I have a call scheduled, yes,” Trump told reporters at the White House when asked if he had spoken to Putin on the issue yet, adding that it would happen “very soon.”

Asked what US intelligence agencies were saying about the situation, Trump added: “We’re in very deep discussions. We’ll be able to report on it probably tomorrow.”

The Wall Street Journal reported that the US State Department had sent Russia a confidential diplomatic communication, known as a demarche, warning Moscow that failure to disclose details runs counter to its international health obligations.