Governments are studying the decision to prohibit youths from using platforms like Facebook and TikTok as worries grow about the potential harm they cause.

The Ukrainian leader rejected the demand, making clear that territorial issues remain unresolved as Ukraine and Europe sent a counterproposal to the United States.

© Mauricio Lima for The New York Times

From Sweden to Brazil, six small companies talk about how they are communicating with their U.S. customers amid uncertainty over Trump’s changing tariffs.