US Secretary of State Mike Pompeo on Tuesday urged US think tanks that seek to co-operate with the State Department to disclose any foreign funding, but without making it legally binding.
Washington has more than 60 think tanks and Mr Pompeo issued a warning of increasing outside influence on US foreign policy.
"We are mindful that some foreign governments, such as those of the People’s Republic of China and the Russian Federation, seek to exert influence over US foreign policy through lobbyists, external experts and think tanks,” he said.
Mr Pompeo asked the organisations to disclose on their websites their sources of foreign funding if they wished to engage with the State Department.
“Disclosure is not a requirement for engaging with such entities," he said.
"Department staff will, however, be mindful of whether disclosure has been made and of specific funding sources that are disclosed when determining whether and how to engage."
Ben Freeman, director of the Foreign Influence Transparency Initiative, told The National: "This is a major step forward for transparency of foreign influence in the US and the first time the US government has called for this level of transparency from think tanks.
“It's critically important because think tanks play an immense role in shaping public policies and the public's perception of US foreign policy.
“Policymakers and the public have a right to know when think tanks are taking big money from foreign powers.”
Daniel Porras, a legal observer, said in a tweet: “If I understand this correctly, think tanks are not bound by US law to disclose, but the State Department might not engage if they are getting funding from unfavourable sources."
