US has granted a similar designation to some 15 countries which allows for access to certain defence and trade privileges, but unlike NATO membership, does not guarantee military protection by Washington.
President Joe Biden has designated Qatar and Colombia as major non-NATO allies of the US, opening the door to closer military and commercial ties with both countries.
Biden's designation of Qatar on Thursday is a big U-turn from the policies of his predecessor Donald Trump who labelled the tiny Arab country as a sponsor of terrorism that led to the economic blockade of the Gulf state by its neighbours.
The designation is granted by the US to close, non-NATO allies that have strategic working relationships with the US military.
Biden promised Qatar's Emir Sheikh Tamim bin Hamad al Thani in January during a meeting at the White House that he would grant Doha the special status.
Qatar has never accepted any of the Trump administration allegations posed against Doha and sought to solve the problems via diplomatic means.
Doha has played an important role in brokering peace between the US and the Taliban that ultimately led to the withdrawal of US-led NATO forces from Afghanistan after 20 years.
Even if the withdrawal was a fiasco for the US, Qatar and NATO ally Türkiye remain major actors in the country. Qatar hosts both US and Turkish military bases.
Biden designates Colombia
Also on Thursday, President Biden tightened relations with Colombia by designating the South American country a "major non-NATO ally" of the United States, opening the door to closer military and commercial ties.
The US president, seated opposite his Colombian counterpart President Ivan Duque and surrounded by ministers and senior officials from both countries, described Colombia as an "essential" partner of the United States.
He called Colombia a "keystone" for economic development and the defense of democracy in South America and thanked Duque for "condemning immediately" Russia's invasion of Ukraine two weeks ago.
Duque said the designation was "taking the bilateral relationship to (its) highest" level ever and expressed his gratitude for US cooperation in the fight against Covid-19 in particular.
The title of "major non-NATO ally" (MNNA) is a legal qualification the United States has granted to some 15 countries.
It allows for access to certain defence and trade privileges, but unlike NATO membership, does not guarantee military protection by the United States.