A journalist who was allowed through airport security wearing a veil which left only her eyes on show has sparked an investigation in Yorkshire.
The airline said procedures were in place to check passenger identity
Newspaper reporter Anila Baig said she was allowed onto a BMI flight from Leeds Bradford Airport to Paris without anyone checking her identity.
Home Office guidelines say people going through passport control should have their faces clearly visible.
Ms Baig was asked to remove her veil by airport security in Paris.
She told the BBC's Asian Network: "Nobody I know who wears the niqab has ever said to me you can just breeze through, so I've never really heard of that happening, and I was completely expecting to have to lift the veil.
"It was a bit of a shock that I didn't have to."
Leeds Bradford Airport said it was the responsibility of the airline to check travellers' identification at check-in and when boarding the plane.
Airline BMI said procedures were in place to verify the identity of all passengers but it would investigate the claims.
It said: "Whilst BMI does not discuss individual security issues or passengers, the airline treats safety and security with paramount importance at all times."