The legal ruling that has blocked a third Heathrow runway could also hit the proposed 'Boris Bridge' across the North Channel from Scotland to Northern Ireland.
The Prime Minister, Boris Johnson, has commissioned a feasibility study into a cross-channel physical link between Northern Ireland and Great Britain.
Mr Johnson has repeatedly spoken about the prospect of a bridge, even though experts have warned that the depth of the Irish Sea and the presence of dumped munitions would cause problems for any such project.
The project could cost a reported £20bn, although Mr Johnson has previously said it would "only cost about £15bn".
But last week's leading judges ruled that the Government must reconsider its support for a third runway because of the environmental impact.
The Court of Appeal concluded that the Secretary of State for Transport failed to take account of the Government's commitments to tackling climate change when setting out support for the project.
A report in the Daily Telegraph at the weekend suggested that "experts" have similar concerns about the environmental impact of the 'Boris Bridge' - in both its construction phase and its future use by cars, coaches and lorries - which could throw a spanner in the works.
The same environmental impact factors could also hit the controversial HS2 railway scheme planned for England.
However, the newspaper did not say where the concerns emanated from.
The Scotland-Northern Ireland bridge proposal is backed by the DUP.
Last night DUP transport spokesman Paul Girvan MP reiterated the party's support for the cross-channel link.
"This is one of the most expensive water crossings anywhere in the British Isles," he said.
"That's why in our 2015 manifesto we called for a feasibility study into a tunnel or a bridge.
"Whilst we want investment in existing roads in Northern Ireland, we must also build infrastructure for the next generation.
"It's natural that a feasibility study would consider all aspects of the project.
"This is a project which we will continues to press the Government to progress, as this is vital transit route for goods throughout the UK and Europe."