The message from many big U.S. companies is loud and clear: We do not support President Trump's travel ban.

But the silence from executives in the region most affected -- north Africa and the Middle East -- is deafening.

The seven countries covered by the ban -- Iran, Iraq, Libya, Somalia, Syria, Sudan and Yemen -- are majority Muslim and include five members of the Arab League, an organization that promotes Arab unity.

Here's why business leaders are saying nothing.

1. The government line

Governments in Saudi Arabia, the United Arab Emirates and Egypt -- three of the biggest regional economies -- have not spoken out against the executive order, which prevents citizens of the banned countries entering the U.S. for at least 90 days.

"Since it is the line their governments have taken, many business leaders may not feel comfortable questioning the ban or questioning their governments line on this," said Trita Parsi, president of the National Iranian American Council.

That's a view shared by Fawaz Gerges, professor of International Relations at the London School of Economics.

"Middle East executives are not as independent as their U.S. counterparts because most of their business depends on the goodwill of Middle Eastern governments."

Related: What is ExxonMobil doing in Iraq?

2. A domestic issue

Trump said the travel ban is in the U.S. interest. He says it will protect its citizens from foreign terrorists.

Some governments and executives in the Middle East appear ready to accept that it's an issue of domestic U.S. policy.

"Issuing a travel ban towards certain countries is an internal matter for the United States, as every country has the right to take what it thinks are the right decisions towards its security and stability," said Salman Al Ansari, president of the Saudi American Public Relation Affairs Committee.

3. Business interests

The United States is a key ally and major trading partner of the Gulf states.

Saudi Arabia is America's biggest trading partner in the Middle East. The two countries traded over $31 billion worth of goods in the first 11 months of 2016.

"Muslim businessmen understand the challenges that the United States are facing. [There's] nothing they can do except voice the issues through their partners in America," said Ahmed Alibrahim, an expert in Saudi-U.S. affairs.

Related: U.S. does $220 billion in trade with Muslim countries

Iraq is the biggest U.S. trading partner affected by the travel ban, and it too has downplayed the move. Prime Minister Haider al-Abadi said his country will not retaliate against the travel ban but is "studying all our options."

Governments don't want to "alienate the Trump administration because they have major investments in the U.S. financial sector," said Gerges of the London School of Economics.

Saudi Arabia alone held $116.8 billion of U.S. government debt as of March 2016, according to the Treasury Department.

4. Regional divisions

Some countries may quietly welcome Iran's inclusion on the list of countries covered by the executive order.

Saudi Arabia and Iran have been at odds with each other after a series of disputes prompted them to cut diplomatic ties with each other last year.

Gulf countries have also been critical of the Iran nuclear deal and strengthening American-Iranian relations under the Obama administration.

"Many of the countries in the GCC are currently obsessed with Iran, and as a result are staying quiet on these issues in the hope this is a sign that Trump is going to get really tough on Iran," said Parsi.