Donald Trump is building a new liberal world order to prevent wars and create prosperity, Mike Pompeo has said.
The US secretary of state blamed Iran and China for instability in the world at a NATO meeting of foreign ministers in Brussels.
"In the finest traditions of our great democracy, we are rallying the noble nations to build a new liberal order that prevents war and achieves greater prosperity," he said.
"Under President Trump, we are not abandoning international leadership or our friends in the international system."
Despite the US president's mantra "America First", Mr Pompeo said Washington was acting unilaterally – as he blamed Iran and China for global instability.
He said: "Even our European friends sometimes say we're not acting in the free world's interest. This is just plain wrong.
"We are acting to preserve, protect, and advance an open, just, transparent and free world of sovereign states.
"This project will require actual, not pretend, restoration of the liberal order among nations.
"It will require an assertive America and leadership from not only my country, but of democracies around the world."
Mr Pompeo told foreign ministers that the US is urging the World Bank and the International Monetary Fund to reduce funding to countries such as China, as he said they already have access to financial markets to raise capital.
He also said organisations including the UN, EU, African Union and IMF have become corroded and are in dire need of change.
In a speech to the German Marshall Fund in Brussels, Mr Pompeo said the US would call out "bad actors" that have exploited loopholes in these organisations for their own gain.
The US president has continually accused European NATO members of failing to spend enough on their own defence, instead over-relying on Washington.
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