German Chancellor Angela Merkel addresses at the World Economic Forum in Davos, Switzerland, Thursday, Jan. 23, 2020. The 50th annual meeting of the forum is taking place in Davos from Jan. 21 until Jan. 24, 2020. (AP Photo/Markus Schreiber)
Swedish climate activist Greta Thunberg, center, is pictured during a "Fridays for Future" demo on the final day of the 50th annual meeting of the World Economic Forum, WEF, in Davos, Switzerland, Friday, Jan. 24, 2020. (Gian Ehrenzeller/Keystone via AP)
United Nations Secretary-General Antonio Guterres attends a session during the World Economic Forum in Davos, Switzerland, Thursday, Jan. 23, 2020. The 50th annual meeting of the forum is taking place in Davos from Jan. 21 until Jan. 24, 2020 (AP Photo/Markus Schreiber)
Finland's Prime Minister Sanna Marin addresses the World Economic Forum in Davos, Switzerland, Thursday, Jan. 23, 2020. The 50th annual meeting of the forum is taking place in Davos from Jan. 21 until Jan. 24, 2020. (AP Photo/Markus Schreiber)
Christine Lagarde, President, European Central Bank, left, and Steven Mnuchin, Secretary of the Treasury of the United States address a plenary session on the final day of the 50th annual meeting of the World Economic Forum, WEF, in Davos, Switzerland, Friday, Jan. 24, 2020. The meeting brings together entrepreneurs, scientists, corporate and political leaders in Davos from January 21 to 24. (Alessandro della Valle/Keystone via AP)
Climate activist Vanessa Nakate, Luisa Neubauer, Greta Thunberg, Isabelle Axelsson and Loukina Tille, from left, arrive for a news conference in Davos, Switzerland, Friday, Jan. 24, 2020. The 50th annual meeting of the forum is taking place in Davos from Jan. 21 until Jan. 24, 2020 (AP Photo/Markus Schreiber)
Pakistan's Prime Minister Imran Khan addresses the World Economic Forum in Davos, Switzerland, Wednesday, Jan. 22, 2020. The 50th annual meeting of the forum is taking place in Davos from Jan. 21 until Jan. 24, 2020. (AP Photo/Markus Schreiber)
In this photo made available by Clarence House, Britain's Prince Charles shakes hands with Climate activist Greta Thunberg, after he delivered a speech, at the World Economic Forum in Davos, Switzerland, Wednesday, Jan. 22, 2020. (Clarence House via AP)
World Economic Forum founder Klaus Schwab, Ivanka Trump, adviser and daughter to the US president, and Swiss defense minister Viola Amherd, from right, applaud after the last plenary session on the final day of the 50th annual meeting of the World Economic Forum, WEF, in Davos, Switzerland, Friday, Jan. 24, 2020. The meeting brings together entrepreneurs, scientists, corporate and political leaders in Davos from January 21 to 24. (Alessandro della Valle/Keystone via AP)
US President Donald Trump leaves after a news conference at the World Economic Forum in Davos, Switzerland, Wednesday, Jan. 22, 2020. Trump's two-day stay in Davos is a test of his ability to balance anger over being impeached with a desire to project leadership on the world stage. (AP Photo/Evan Vucci)