In a significant expansion of gun rights, the Supreme Court ruled that Americans have a right to carry firearms publicly for self-defence.
A decision President Biden has called "deeply disappointing."
The move follows a string of recent mass shootings in Texas, New York and California.
And, it is expected to allow more people to legally carry guns on the streets of the nation's largest cities, including New York, Los Angeles and Boston.
Around a quarter of Americans live in states expected to be affected by the ruling, which had previously been struck down a New York gun law.
The law required people to demonstrate a particular need for carrying a gun to get a license to carry one in public.
Backers of New York's gun law argued that striking it down would lead to more guns on the streets and higher violent crime rates.
Biden stated that the ruling "contradicts both common sense and the Constitution and should deeply trouble us all."
He urged states to pass new laws and said, "I call on Americans across the country to make their voices heard on gun safety. Lives are on the line."
However, defending the decision, Justice Clarence Thomas wrote that the Constitution protects "an individual's right to carry a handgun for self-defence outside the home."
Lawmakers say the requirement violates the Second Amendment right to "keep and bear arms."
The Biden administration had urged the justices to uphold New York's law.
Governor of New York Kathy Hochul said the ruling comes at a difficult time when the city is still mourning the deaths of 10 people in a mass shooting at a supermarket in Buffalo.
"This decision isn't just reckless. It's reprehensible. It's not what New Yorkers want," she said.
But Tom King, president of the plaintiff New York State Rifle and Pistol Association, said he was relieved.
"The lawful and legal gun owner of New York State is no longer going to be persecuted by laws that have nothing to do with the safety of the people and will do nothing to make the people safer," he said.
"And maybe now we'll start going after criminals and the perpetrator of these heinous acts."
Those arguing against the majority ruiling , Justice Stephen Breyer focused on the toll taken by gun violence.
"Since the start of this year alone (2022), there have already been 277 reported mass shootings—an average of more than one per day, "Breyer wrote.
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Gun violence, which was already rising during the coronavirus pandemic, has spiked anew.
In most of the country, gun owners have little difficulty legally carrying their weapons in public.
But that had been harder to do in New York and the handful of states with similar laws.
New York's law, which has been in place since 1913, says that to carry a concealed handgun in public, a person applying for a license must show "proper cause," a specific need to carry the weapon.
The state issues unrestricted licenses where a person can carry their gun anywhere and restricted rights that allow a person to hold the weapon for specific purposes such as hunting and target shooting or to and from their place of business.
The Supreme Court last issued a significant gun decision in 2010.
In that decision and a ruling from 2008 the justices established a nationwide right to keep a gun at home for self-defence.
The court's decision is somewhat out of step with public opinion and at odds with much of the rest of the world's perception on guns in America.
About half of voters in the 2020 presidential election said gun laws in the US should be made more strict, according to AP VoteCast, a comprehensive survey of the electorate.
An additional third said laws should be kept as they are, while only about 1 in 10 said gun laws should be less strict.
About 8 in 10 Democratic voters said gun laws should be stricter, VoteCast showed.