A Victorian Labor MP has been denied entry to the United States while on a taxpayer funded delegation.

Lebanese-born Khalil Eideh was stopped at Vancouver in Canada after a United Airlines staffer told him he was not allowed to board a flight to Denver with the rest of the group.

“The United Airlines staff knew he had been denied entry to the US before any of us,” Sex Party MP Fiona Patten told AAP from Denver on Friday.

“He was incredibly upset… (he was) disbelieving.”

Ms Patten said Mr Eideh was not told why he wasn’t allowed on the plane.

Liberal MP Martin Dixon, Labor MPs Geoff Howard and Natalie Suleyman, and Victoria Police Assistant Commissioner Rick Nugent are also on the study trip.

Every MP in the delegation had been issued with official passports and visas weeks before the trip.

“It was shocking, we had all received the same US visa and were all traveling on official passports,” Ms Patten said on Twitter.

It’s understood a Victorian government trade official is with Mr Eideh in Vancouver.

It was shocking we had all received the same US visa and were all traveling on official passports. https://t.co/xqPe8959aX

— Fiona Patten (@FionaHPatten) July 28, 2017

A spokesperson said the government had asked for an explanation.

“The Victorian Government has made representations to the Department of Foreign Affairs and Trade and have asked them to seek an explanation from the US authorities as to why a Victorian Member of Parliament was refused entry to the United States,” the spokesperson told The New Daily.

The group had been in Europe and Canada studying drug laws and were due to fly to Denver on the next leg when Mr Eideh was blocked at the airport.

Lebanon was not affected by the travel ban US President Donald Trump put in place. Mr Eideh has ties to Syria, according to Herald Sun.

He has voiced support for President Bashar Hafez al-Assad.

The US Embassy in Canberra said it could not comment on individual cases.

The New Daily has reached out to US Customs and Border Protection.