US presidential hopeful Joe Biden has promised to end "forever wars", including pulling most troops out of Afghanistan and ending support for the Saudi intervention in Yemen.
The former vice-president to Barack Obama is bidding to be the Democratic Party's nominee to run against Donald Trump in next year's election.
Speaking in New York, Mr Biden criticised Mr Trump for "embracing dictators who appeal to his vanity" and emboldening the rise of nationalism and xenophobia.
He also accused the president of damaging America's reputation and ability to lead on the world stage.
Since taking power in 2016, Mr Trump has pulled the US out of two landmark agreements – the Paris climate accord and the Iran nuclear deal – and threatened to leave NATO.
Mr Biden said he would re-engage with Iran if it complies with the terms of the 2015 deal, and would immediately rejoin the Paris accord, while also urging the likes of China to aggressively cut carbon emissions.
The 76-year-old pledged to "end the forever wars in Afghanistan and the Middle East" – but said military force would always be an option.
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However, he said any such action must be a "last resort" with an "achievable mission".
Mr Biden said most US combat troops would leave Afghanistan, with America "narrowly focusing our mission" in the region.
Mr Trump's high-profile meetings with North Korean dictator Kim Jong Un appear to have helped curtail the country's missile tests, but Mr Biden said he would target tougher commitments from the country on abandoning its nuclear programme.
Among his domestic plans are ending the travel ban on people from Muslim-majority countries and stop segregating migrant families at the US-Mexico border.
Ahead of Mr Biden's speech, the Republican National Committee criticised his judgement on foreign policy, saying that he had advised Mr Obama not to carry out the raid that killed Osama bin Laden and Read More – Source