Ruth Christoffersen has fought for improvements

Ruth Christoffersen, from Newport, south Wales, lost her 28-year-old daughter Emma to air-related DVT after a flight from Australia in 2000.

She has since become a tireless campaigner, fighting to raise awareness of the dangers of the condition.

On Saturday she will be joined by relatives of other victims in John Frost Square, Newport, to gather support for a change in legislation which would make airlines take responsibility for the health of passengers.

The families of those who died have formed a support and campaigning group, Families of Victims of Air-Related DVT (Varda).

They will be joined by Vale of Glamorgan MP John Smith, who has raised their concerns in the House of Commons.

Emma had just returned from Sydney

In July, three senior judges reinforced a decision that airlines could not be held liable if passengers developed DVT - under the terms of the 1929 Warsaw Convention.

Relatives had joined together to appeal against the original ruling, but described the decision to dismiss their appeal as a "major blow".

They said they would be prepared to take their fight to the House of Lords.

A court last year ruled the airlines were not liable, but gave the victims leave to appeal. Many of the 55 claimants in that case could not afford to continue the legal process.

The ruling in December was based on the 1929 Warsaw Convention which says DVT cannot be classed as an "accident", and therefore airlines cannot be held responsible.

In deep vein thrombosis, a blood clot which develops, usually in the leg, when movement is restricted.

It can be fatal if the clot reaches the lungs or brain.

Several British travellers have died after flights and the claimants accused the airlines of not warning passengers about the risks.