Victorian State MP Khalil Eideh, who was blocked from entering the United States while on an overseas study tour, has arrived home "exhausted, very, very disappointed [and] frustrated" by his treatment.

Key points: Victorian State MP Khalil Eideh is a dual Australian and Syrian citizen

Victorian State MP Khalil Eideh is a dual Australian and Syrian citizen He was blocked from entering the US, despite holding a visa

He was blocked from entering the US, despite holding a visa Labor Senator Kim Carr says the decision shows "chaos reigns" in Trump's America

The Upper House MP, who was born in Lebanon, was part of a group of MPs examining the effectiveness of drug laws and regulations in Europe and North America.

But when he went to fly from Vancouver to Denver he was told his flight had been cancelled by the US.

"[They gave me] no explanation whatsoever, at first they couldn't find my name. When I gave them my itinerary they said 'ah yes, unfortunately it's blocked and we can't take you on the plane'," he said.

Mr Eideh said his family is from Syria, which is on the list of countries targeted by US President Donald Trump's travel restrictions, and he has joint Australian and Syrian citizenship.

"One of the ministers was saying it could be because of the Trump decision … Syria is included in these countries. I'm not sure if that's the reason," he said.

"To me it is unacceptable, because I'm representing the Australian people, the Victorian people."

He said he had visited Syria last Christmas, but said that should not have affected his visa "at all".

"We've got family in Syria … we do visit," he said.

"They know that, they asked me the question before they issued the visa.

"If there was any issue they should've told me, they've got five weeks to do that, not just be stopped at Vancouver and not allowed to board the plane and join my colleagues to do the business our Parliament asked us to do."

Mr Eideh said it was his first trip to the US, and the first time he had been stopped at an airport.'

'Australia is an ally'

Federal Labor senator Kim Carr said Mr Eideh had been the "victim of Trumpism".

"What we're seeing here is the chaos that reigns in the United States," he said.

"We simply can not understand why an ally like Australia, a great military partner like Australia, should be treated in this way, [why] a member of an Australian Parliament on the business of the Victorian people should be treated in this manner.

"There is absolutely an extraordinary circumstance where we have no explanation for this behaviour."

Mr Eideh also travelled with three other state MPs to Syria in 2007, a parliamentary travel report showed.

The MPs visited Syria and Dubai to "look at trade issues in the fast-growing country Qatar" and also to "witness the refugee crisis that had been created in the Middle East by the invasion of Iraq".

Mr Eideh and the delegation met with the vice-president of al-Assad's Baathist Party, Najah Al-Attah, as well as visiting the Syrian Parliament and met with the speaker and ministers, and several governors.

Mr Eideh wrote to president Bashar al-Assad in 2002, which he later said was taken out of context.

Arriving home at Melbourne Airport, Mr Eideh said he did not have a relationship with the governing party in Syria.

When asked if he supported the Syrian Government he said his loyalty was to Australia, where he has lived for 47 years since he was 15 years old.

"Like Australia, the United States administers a strict entry regime and the decision on who can enter the country is a matter solely for the US Government," the spokesperson said.

"Australian consular officials stand ready to provide assistance, should it be required."

US Customs and Border Protection branch chief Jaime Ruiz said having a valid visa did not guarantee entry into the country.

"A visa allows a traveller to knock at the door — travel to a port of entry, airport or land border crossing and request permission to US Customs and Border Protection," he said on Friday.

"All travellers must clear admissibility laws."

He said only a small number of the more than 1.2 million people who came to the US each day were denied entry.