Fears over the safety of the giant gas pipeline destined for the Pembrokeshire countryside have heightened after it emerged that 15 people were killed in a gas pipe explosion in Belgium just seven months ago.

Some of the dead are reported to have been killed as they went to investigate a leak in the pipeline carrying gas from the port of Zeebrugge on the Belgian coast to France.

Concerns have been raised by Gordon Main, of pressure group Safe Haven, over stress corrosion cracking (SCC) - a form of corrosion that can lead to sudden catastrophic failure in pipelines.

Mr Main, and farmers who are affected by the pipeline, are also worried about the high pressure gas passing through the pipelines.

Mr Main challenged Transco's claims that corrosion could not occur in Pembrokeshire because the pipe would have to be at 50 degrees centigrade and experience certain soil conditions unknown in the county.

"I checked with a chartered welder and pipeline inspector in Canada who confirmed this was not the case," said Mr Main.

"He did not know of an underground pipeline anywhere in the world that reached temperatures of 50 degrees centigrade, yet SCC occurs in many countries.

"It occurs in ph acid and ph neutral soils - Pembrokeshire has both in abundance." But a Transco spokesman insisted: "Our engineers say that this is definitely not a problem in the UK. We transport only dry gas, so corrosion on the inside of the pipe and stress corrosion have no means of developing.

"Transco has 280 kilometres of 48 inch diameter pipe in the UK and we have had no problems.

"Transco has an exemplary safety record and is a world leader in gas pipeline safety." But this has done little to allay concerns among the people directly affected by the Pembrokeshire pipeline, due to be laid next spring.

Farmers, landowners and their agents met representatives of the gas company, Transco, last week amid accusations that the business was keeping them in the dark.

Jill Gibson, who organised the meeting on behalf of Farm Crisis Network, said Transco had publicly recognised that communications had been poor.

The first some farmers knew that a pipeline might be crossing their land was when surveyors and analysts turned up unannounced.

"There was recognition that there needs to be a more open engagement with landowners," said Caroline Davidson, of Transco. "After the meeting, farmers expressed relief that some dialogue was now taking place.

"The last thing we want to happen is for farmers to lose out. We will work with them to address their specific problems. The next time we meet with them will be on an individual basis."

Around 100 farmers attended the meeting in Haverfordwest and many were keen to express their concerns.

The four-foot diameter pipeline will split in half Tony Young's organic livestock farm at Upper Bastleford, Rosemarket.

"It is going to mean a major upheaval," admitted Mr Young. His son, Nick, called on Transco to undertake a full risk assessment before it goes ahead with the project.

"They agreed to this which is extremely important, because there are people living near this pipeline who won't have any say about it whatsoever," said Tony Young.

Transco described its safety record as impeccable but could appreciate the concerns. "Safety is paramount to Transco in every aspect of the project.

We operate under very strict environmental and safety controls and ensure that this is the case with all our contractors also," said spokeswoman Caroline Davidson.