California, US (BBN) - Amazon, Microsoft and Expedia have backed a legal challenge to President Donald Trump's immigration curbs.
The lawsuit, filed by Washington Attorney General Bob Ferguson, aims to prove that President Trump's order, which temporarily bars nationals from seven Muslim-majority countries from entering the US, is unconstitutional, reports BBC.
Amazon's Jeff Bezos said his firm had "prepared a declaration of support".
Microsoft said it would be happy to testify "if needed".
In an email to employees, Mr Bezos said: "We're a nation of immigrants whose diverse backgrounds, ideas and points of view have helped us build and invent as a nation for over 240 years. No nation is better at harnessing the energies and talents of immigrants. It's a distinctive competitive advantage for our country - one we should not weaken."
Mr Bezos said that the firm has also reached out to congressional leaders to explore legislative options.
BARRIERS TO TALENT
It is the latest protest in a chorus of disapproval from Silicon Valley over the controversial executive order signed by President Trump.
Many firms have expressed concern about the order's effect on employees, with some saying it violates company principles.
Apple and Twitter have criticised it, while Netflix's chief executive Reed Hasting declared it "unAmerican."
AirBnB co-founder Brian Chesky offered free housing to anyone caught outside the US, unable to return home, while Google revealed that more than 100 staff members were directly affected.
In a statement Google said: "We're concerned about the impact of this order and any proposals that could impose restrictions on Googlers and their families, or that could create barriers to bringing great talent to the US.
"We'll continue to make our views on these issues known to leaders in Washington and elsewhere."
The White House has defended the new rules, saying that the majority of Americans agree with the president.
"They recognise that the steps that he's taken were to keep this country safe and to make sure that we didn't look back and say, 'I wish we had done the following,'" said spokesman Sean Spicer.
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