Think tank experts often provide advise to the US executive branch, but very few are actually called by the US president himself to provide direct advice.
President Joe Biden, however, has been more receptive to outside voices, and he sometimes convenes leading think tank scholars to help guide his thinking and decisions.
Here is more from the Washington Post:
Michael McFaul, a former U.S. ambassador to Russia under President Barack Obama, briefed Biden with other experts before the Russian invasion of Ukraine and before the president’s 2021 meeting with Russian President Vladimir Putin in Geneva.
McFaul was among a socially distanced group that met to discuss Ukraine in the East Room earlier this year, along with former diplomat Richard Haass, journalist Fareed Zakaria, analyst Ian Bremmer, former National Security Council adviser Fiona Hill and retired Adm. James G. Stavridis, a former Supreme Allied Commander of NATO.
Amb. McFaul is the Director of the Freeman Spogli Institute for International Studies at Stanford University and is also a Senior Fellow at the Hoover Institution.
Richard Haass in the President of the Council on Foreign Relations (CFR), and Fiona Hill is a Senior Fellow at the Brookings Institution.
Stavridis once led the US Navy's premier operational think tank for innovation, Deep Blue.