WASHINGTON- Afghanistan, India and Pakistan were among 11 countries singled out by U.S. intelligence agencies on Thursday as being "highly vulnerable" in terms of their ability to prepare for and respond to environmental and societal crises caused by climate change.

In a new National Intelligence Estimate, the Office of Director of National Intelligence (ODNI) predicts that global warming will increase geopolitical tensions and risks to U.S. national security over the next four decades, a senior intelligence official involved in drafting the report said.

Such estimates are broad U.S. intelligence community assessments. Thursday's report identifies as particular "countries of concern" Afghanistan, India, Pakistan, Myanmar, Iraq, North Korea, Guatemala, Haiti, Honduras, Nicaragua and Colombia.

Heat, drought, water availability and ineffective government make Afghanistan specifically worrying, the official said. Water disputes are also a key "geopolitical flashpoint" in India and the rest of South Asia.

The report identifies two additional regions of concern to U.S. intelligence agencies. Climate change is "likely to increase the risk of instability in countries in Central Africa and small island states in the Pacific, which clustered together form two of the most vulnerable areas in the world."

The report notes disparities around global approaches to tackling climate change, saying countries that rely on fossil fuel exports to support their economies "will continue to resist a quick transition to a zero-carbon world because they fear the economic, political, and geopolitical costs of doing so."

The report also notes the likelihood of increasing strategic competition over the Arctic. It says that Arctic and non-Arctic states "almost certainly will increase their competitive activities as the region becomes more accessible because of warming temperatures and reduced ice."

It predicts international competition in the Arctic "will be largely economic but the risk of miscalculation will increase modestly by 2040 as commercial and military activity grows and opportunities are more contested."

(Reporting by Mark Hosenball Editing by Frances Kerry) ((mark.hosenball@thomsonreuters.com;))