Lifesaving treatment and prevention programs for tuberculosis, malaria, H.I.V. and other diseases cannot access funds to continue work.

PEPFAR’s computer systems also are being taken offline, a sign that the program may not return, as Republican critics had hoped.

Pepfar, which is estimated to have delivered lifesaving treatment to as many as 25 million people in 54 countries, faces a funding delay of as long as 180 days.

Wright, the founder of a fracking firm, testified that he would back all forms of low-carbon energy as well as gas, oil and coal.

A new study assesses the effects of sugar-laden beverages on global health, with higher rates of consumption found in Latin America and parts of Africa.

In a landmark international hearing on climate change, a U.S. representative backed the Paris Agreement, but left unanswered questions about U.S. commitments in a Trump presidency.

© Robin Van Lonkhuijsen/Agence France-Presse — Getty Images

The International Court of Justice, the United Nations’ highest judicial body, is beginning landmark hearings on global warming. Here’s a guide.

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What the U.N. negotiations, known as COP, can (and can’t) do to combat climate change.

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