“This action may require those members to leave the country,” Deputy UN Spokesman Farhan Haq told reporters at the daily press briefing, citing the UN-US Headquarters Agreement, which governs the relations between the Organization and the Host country.

“Given the sensitivity of the matter, which is ongoing, we will not comment further at this stage other than to confirm that the Secretary-General will closely follow this matter and engage as appropriate with the Governments concerned,” he said.

News reports suggest that the US Administration on Monday ordered the expulsion of 60 Russians from the US, following similar actions taken by other countries in the wake of the allegation by the United Kingdom that Russia was behind an attack using a deadly nerve-agent in Salisbury on 4 March, which left Sergei Skripal and his daughter, Yulia, hospitalized in critical condition.

On 14 March, the UK brought the charge before an urgent meeting of the UN Security Council, where US Ambassador Nikki Haley said that the US stood in solidarity with the UK in denouncing the “crime” and believed Russia had been responsible for the attack.

At the same meeting, both Russia and the United Kingdom said the incident should be investigated by the Hague-based Organisation for the Prohibition of Chemical Weapons (OPCW), the UN-backed body which works to implement the Chemical Weapons Convention (CWC) and eliminate chemical weapons use, and the threat of their use.

The UK Foreign Ministry announced later that independent investigators from the OPCW were due to arrive in the UK on Monday, 19 March to kick off their probe into the nerve agent used in the Salisbury attack.