A prominent anti-regime Syrian journalist has had her passport confiscated by UK border officials, hindering her ability to work and travel.

Zaina Erhaim, a fierce critic of President Bashar al-Assad, says she was detained and questioned for an hour by officials when she arrived at Heathrow airport from Istanbul on Friday.

She was told that her passport had been reported by Syrian authorities as stolen and would have to be returned to the Syrian government. A spokesperson from the Home Office said that the UK was required to comply as passports are the legal property of the issuing government, rather than the individual holder.

Ms Erhaim wrote on her website that she has not had problems travelling with the passport around Europe before, including a trip to the UK in April.

She also has an older passport she can use to return home to Turkey, but since it has no pages left for visas or stamps, she fears she will in effect be unable to leave the country again.

The Home Office suggested Ms Erhaim seek consular advice on the matter from the Damascus government. She says it will be incredibly difficult to get a new passport issued by a hostile regime.

Robert Fisk: Freedom, democracy and human rights in Syria Show all 3 1 /3 Robert Fisk: Freedom, democracy and human rights in Syria Robert Fisk: Freedom, democracy and human rights in Syria Syrian students hold candles and portraits of President Bashar al-Assad during a demonstration in Damascus last year AFP/GETTY IMAGES Robert Fisk: Freedom, democracy and human rights in Syria Ribal al-Assad: 'The Berlin Wall fell, the Soviet Union collapsed. Syria will change' Robert Fisk: Freedom, democracy and human rights in Syria The late Syrian President Hafez al-Assad, right, with his youngest brother, Rifaat, Ribal-s father, in Damascus in 1984 AFP

Ms Erhaim, originally from Aleppo, has won several international awards for courageous and ethical journalism. She trained hundreds of citizen reporters, including many women, to report independently and accurately on the horrors of Syria’s six-year-long civil war before finally being forced to flee last year.

She had been travelling to the UK to talk at an event about front line reporting with BBC journalist Kate Adie at the Kew Literary Festival.

Jodie Ginsberg, chief executive of the Index on Censorship, who invited Ms Erhaim, told The Observer: “I am appalled and frankly ashamed at the treatment of Zaina Erhaim by the UK. This is a woman who has risked her life simply to do what every good journalist aspires to do – bring both sides of the story – in an area of conflict that is also her home.”