A man leaves the international arrivals hall at Washington Dulles International Airport after a US appeals court rejected a government request to immediately reinstate US President Trump’s travel ban.

“Islamophobia” in parts of the world is fueling terrorism, the head of the United Nations said on a visit to Saudi Arabia Sunday, as anti-immigrant sentiment rises in some countries.

UN Secretary-General Antonio Guterres made the comment to reporters after talks with Saudi King Salman, Crown Prince and Interior Minister Mohammed bin Nayef, and Deputy Crown Prince Mohammed bin Salman.

“One of the things that fuel terrorism is the expression in some parts of the world of Islamophobic feelings and Islamophobic policies and Islamophobic hate speeches,” Guterres said at a joint news conference with Saudi Foreign Minister Adel al-Jubeir.

“This is sometimes the best support that Daesh can have to make its own propaganda,” Guterres said, using an Arabic acronym for the Islamic State group of Sunni extremists in Syria and Iraq.

The militant group has also claimed deadly attacks in Saudi Arabia and in Europe.

Anti-immigration politicians including France’s Marine Le Pen have seen their popularity rise after an influx to Europe of migrants, many of them Muslims fleeing wars in Syria and elsewhere.

US President Donald Trump issued an order in late January that denied entry to all refugees for 120 days.

It also blocked travelers from Iran, Iraq, Libya, Somalia, Sudan, Syria and Yemen for 90 days. Refugees from Syria were blocked indefinitely.

But the order has faced obstacles and on Thursday an appellate court decided unanimously to maintain a block on Trump’s order.

Syria’s conflict has created 4.8 million refugees and killed more than 310,000 people since it began with anti-government protests in March 2011.

Guterres said “we will never be successful in fighting terrorism in Syria if an inclusive political solution is not found for the Syrian people.”

A new round of UN-sponsored peace talks is scheduled for February 20 in Geneva.

Guterres also told journalists: “Saudi’s stability is a model for the pursuit of change and growth”.

He stressed that “the cooperation between the United Nations and Saudi Arabia, is key in the fight against terrorism,” explaining that the “United Nations is working to help member states in the fight terrorism”.

On the disruption of humanitarian aid in Yemen, he said: “We urge Yemen parties not to take advantage of humanitarian aid, condemn if they do.”

And he added that the UN envoy to Yemen had his ‘full support’, which came days after Houthi militia had demanded he did not renew the diplomat’s term due to what it alleged was bias against the Iranian-aligned movement.

Guterres arrived in Saudi Arabia from Turkey and is to be in Dubai on Monday for the World Government Summit during his regional tour.