Amid diplomatic tensions between host South Africa and the Trump Administration, the U.S. will be represented at a meeting of foreign ministers by the acting ambassador to South Africa.

A G-20 meeting would normally be an opportunity for a U.S. secretary of state to push for support on U.S. positions.

The Treasury secretary is the second top U.S. official not to attend the Group of 20 gatherings because of rising tension with South Africa over its land policies.

U.K. Foreign Secretary David Lammy said he saw no appetite for peace from Russia in Ukraine after listening to a speech by Russia's top diplomat at a tense Group of 20 meeting in South Africa on Thursday.