Amazon is exploring legal options to challenge US President Donald Trump’s controversial executive order, which bans immigration from seven specific countries.

In a note to employees, Amazon CEO Jeff Bezos said that the company’s policy team had reached out to congressional leaders from both parties and that its legal team had prepared a declaration of support for the Washington State Attorney General who will be filing suit against the order.

“We’re a nation of immigrants whose diverse backgrounds, ideas, and points of view

jeff bezos Amazon fights Trump immigration order
Jeff Bezos, Amazon CEO.

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.”

Bezos told employees affected by the order that “the full extent of Amazon’s resources are behind you.”

Amazon is advising employees from seven Muslim-majority nations to avoid traveling outside the US. The company said it is drawing up contingency plans for employees affected by the order who are currently abroad.

Amazon is one of several tech giants that are opposing the order. Google, Facebook and Microsoft have criticised the executive order, which bans citizens from Iraq, Iran, Syria, Somalia, Sudan, Libya, and Yemen from entering the US on any visa category.

READ: Tech giants unite in Silicon Valley backlash at Trump immigration ban

The White House has however defended the new rules. White House Press Secretary Sean Spicer was quoted by The Wall Street Journal as saying, “A 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.’ ”