The ban targets people from Iran, Libya, Somalia, Syria and Yemen

The US Supreme Court has upheld Donald Trump’s travel ban targeting a number of Muslim-majority countries.

The nine-member court handed down its ruling today – finding that the ban does not violate either US immigration law – or the first Amendment to the US Constitution, which blocks the Government from favouring one religion over another.

The 5-4 verdict is being hailed as a major victory for the US President and a significant blow to anti-discrimination campaigners, who had argued that the legislation represents an unlawful 'Muslim ban.'

Within minutes of the ruling this afternoon, President Trump tweeted: Wow!

The Supreme Court ruling ends months of legal argument, after lower US courts blocked the current version of the ban, announced in September – as well as two prior versions – on constitutional grounds.

The current version prohibits most people from Iran, Libya, Somalia, Syria and Yemen entering the US.

It has largely been in effect since last December, even as the legal challenge was ongoing.

Opponents warn the ban has done nothing for national security and is in violation of constitutional protections against religious discrimination.

Neal Katyal, the lawyer who argued against the ban, tweeted his disappointment at the decision – but warned President Trump not to take the ruling as an "approval to continue attacking our Constitution" adding that campaigners "will always fight it."

“We continue to believe, as do four dissenting judges, that the travel ban is unconstitutional, unprecedented, unnecessary and un-American,” he said.

Writing on behalf of the court, US chief Justice john Roberts said the Government had “set forth a sufficient national security justification” to defeat the legal challenge, however he noted that the court had “expressed no view on the soundness of the policy.”

He emphasised the importance principle of non-discrimination in US history and noted that America is “a great country because we share the same values of respect and dignity and human worth.”