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Russia said on Friday that it will add UK think tank Chatham House to a blacklist of "undesirable" international organisations, calling it a threat to national security.
While the Russian announcement did not give any specific reason for the decision, it comes after Britain's strong support for Kyiv after Russia launched military operations in Ukraine.
Chatham House is the informal name for The Royal Institute of International Affairs, a respected, more than century-old research institute in London that focuses on international affairs and is widely cited by media.
Ukrainian President Volodymyr Zelenskyy's chief of staff Andriy Yermak and Foreign Minister Dmytro Kuleba have recently taken part in events organised by Chatham House.
It recently held an online seminar titled "Aggression against Ukraine: Holding Russia accountable".
Russia's prosecutor general's office said in a statement that it had taken the decision "to declare the activities of the international NGO undesirable on Russian soil".
It said it had found, based on "materials" received, that Chatham House "presents a threat to the constitutional order and security of Russia".
Under a controversial law passed in 2015, Russia can ban overseas organisations considered a threat to national security.
The list maintained by the justice ministry targets organisations in the US, such as the National Endowment for Democracy and the US-government funded Atlantic Council.
It also features groups controlled by people long reviled by Russian authorities, including Hungarian-born billionaire George Soros and Russian former tycoon Mikhail Khodorkovsky.
Baptism of fire for new Chatham head
The blacklisting comes just days after the think tank announced the appointment of Bronwen Maddox as its new director and chief executive.
She arrives from the Institute for Government, an independent think tank in London that promotes better government.
Ms Maddox was previously foreign editor, chief foreign commentator and US editor at The Times, and before that, she ran award-winning investigations and wrote economics editorials for the Financial Times, after a career as an investment analyst in the City. She writes frequent op-ed columns for the Financial Times and broadcasts widely.
She succeeds Dr Robin Niblett CMG who is standing down in the summer after 15 years in the role. She will take up the position at the end of August.
‘I am honoured and delighted to become Chatham House’s next director," Ms Maddox said.
"It’s a momentous period in international affairs and Chatham House, with its reputation for rigour, independence and expert analysis, has a unique role to play in assessing these changes and prompting solutions to confront them – as it shows every day.
"I look forward to the privilege of working with its teams, and the many others who have come together to advance its work."