One in four companies say that US President Donald Trump’s attempt to ban travel from Muslim-majority countries has hurt business travel, and about one-third say they expect further reductions now that the US Supreme Court has affirmed Trump’s authority to impose such restrictions.

The member survey by the Global Business Travel Association (GBTA) found bad news across the board arising from Trump’s policies on travel and immigration.

For example, 62 per cent of GBTA members who are US based travel buyers said that Trump has had a negative effect on business travel, while more than half (52 per cent) noted rising concern about harassment of international business travellers at US borders.

The majority of business travellers worried that the policies could, in turn, make international travel more difficult for Americans as well as complicating travel into the US, and increasing threats against American travellers abroad.

More than one-third of European members of GBTA said Trump’s policies have resulted in reductions in their business travel.

“GBTA is deeply concerned about the long-term impact of these survey results, and the global perception of doing business with the United States,” the group said in a press statement.

“For every action, there is an equal and opposite reaction, and as the United States changes its policies about inbound travel, others are likely to do the same.”

GBTA estimated that for every one per cent decrease in business travel spending, the US economy loses 74,000 jobs, $5.5 billion in GDP, $3.3 billion in wages, and $1.3 billion in taxes.