Eight retired seamen from Milford Haven are claiming that arrangements to ship liquefied natural gas (LNG) to the port are potentially dangerous.
There are calls for the LNG project at Milford Haven to be reassessed
The sea pilots' complaint is highlighted in a BBC Wales documentary.
The port authority, which is responsible for marine safety, said its arrangements were safe and effective.
Last week the Court of Appeal said local authorities had fully assessed the risks after campaigners had tried to have planning consent reviewed.
Despite that ruling, the, Plaid Cymru MP for Carmarthen East and Dinefwr Adam Price has called for a reassessment of the entire project.
In Tuesday's Taro Naw programme at 2025 on S4C, he says there are many questions which had not been answered by the authorities.
The UK energy minister denies the scheme is being railroaded through
"It has to be a worry that those who are making the decisions, the Department of Trade and Industry (DTI) and Ofgem, [the gas and electricity regulator], are so keen to plug the UK energy gap that there may be a conflict of interest between safety and the need to ensure an energy supply," Mr Price said.
But the UK Energy Minister Malcolm Wicks said it was not the case that the scheme was being railroaded through.
"The development has gone through planning and the Health and Safety Executive have given it a green light, so I'm satisfied that safety has been looked after," Mr Wicks said.
Meanwhile the retired pilots, who have decades of experience steering large crude oil carriers through the navigation channels, have written to the DTI and Milford Haven Port Authority to complain that the Exxon Mobil LNG terminal at the port is potentially dangerous.
"Tankers who have to pass the jetty will be very close to the LNG ships at berth," said retired pilot Ian Evans.
"There have been several accidents there when the terminal was used by Esso tankers; if there is any human or mechanical error, there would be a disaster."
Ted Sangster, chief executive of the port authority said they were more than happy to meet the retired pilots to show them their arrangements for shipping LNG were safe and effective.
He said: "Our current pilots are modern and up-to-date and much more heavily trained than the retired seamen; they have more tools available to them (like simulators); and our marine operations are much more subject to third party scrutiny."
Campaigners opposed to the LNG terminals last week lost an appeal to seek a judicial review of planning consent.
The LNG opponents had claimed at the Court of Appeal that if disaster struck, 20,000 people could be at risk of dying from a "highly inflammable cloud".
But judges ruled the local authorities had fully assessed the risks.