Apple, Google, Microsoft and Facebook take on Donald Trump

Satya Nadella (Getty)
Satya Nadella (Getty)

The leaders of some of the United States' biggest corporations have spoken out against Donald Trump's immigration crackdown.

The US President has signed an executive order blocking entry to the US for citizens of Syria, Iraq, Iran, Sudan, Libya, Somalia and Yemen - including people from other countries with dual citizenship with one of those seven.

Mr Trump says it's to stop terror attacks.

Google has reportedly recalled its staff to the US, hoping to get back "more than 100" of its staff who might not be able to get back in once the order is fully implemented.

"It's painful to see the personal cost of this executive order on our colleagues," Google chief executive Sundar Pichai wrote in a leaked memo. "We've always made our view on immigration issues known publicly and will continue to do so."

Apple was founded by Steve Jobs, the son of a Syrian immigrant. Its current chief executive, Tim Cook, has sent an email to employees, saying the company cannot support Mr Trump's immigration policy.

"Apple would not exist without immigration, let alone thrive and innovate the way we do," Mr Cook wrote.

"Apple is open - open to everyone, no matter where they come from, which language they speak, who they love or how they worship. Our employees represent the finest talent in the world, and our team hails from every corner of the globe."

Apple is the largest company in the US, by market cap. The second biggest is Alphabet, which owns Google. The third is Microsoft, which is currently led by India-born Satya Nadella. 

"As an immigrant and as a CEO," Mr Nadella wrote on networking site LinkedIn, "I've both experienced and seen the positive impact that immigration has on our company, for the country, and for the world.

"We will continue to advocate on this important topic."

On Saturday (NZ time) Facebook founder Mark Zuckerberg said under Mr Trump's immigration policies, he would never had met his wife.

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