The completion of the Highland Railway between Beddgelert and Porthmadog could be delayed by up to a year due to a funding dispute
The opening of the final stage of a 25-mile (40km) narrow gauge railway across Snowdonia has been further delayed by a dispute over an unpaid bill.
Welsh Highland Railway (WHR) claim it is owed around £250,000 by the assembly government agency, the North Wales Trunk Road Agency.
It said the money was for work done on its behalf to a bridge in Porthmadog.
But the assembly government said it had only agreed to contribute towards part of the work and the bill was excessive.
The £28m project to reinstate the Welsh Highland Railway between Caernarfon and Porthmadog was due to be completed in Easter - with the track across the Snowdonia National Park being reopened in stages.
The line has already been opened as far as Hafod y Llyn through the Aberglaslyn pass between Beddgelert and Porthmadog.
The dispute is based on work carried out on a retaining wall damaged on the land side of the Glaslyn near Britannia Bridge near the Welsh Highland's station at Porthmadog.
Railway general manager Paul Lewin said the retaining wall had been damage during a storm on the tidal river.
The company used the same contractors to carry out work on the railway line and the wall, he said.
"They've done a lovely job, and it needed to be done," he added.
"But until we've recovered the money, unless some rabbit is pulled out, we have to plan our business," he said.
The money will contribute towards signalling and other commissioning work on the last bit of line.
He added however that if the dispute is settled early enough it may be possible to run some trains through to Porthmadog at the end of 2010, but a full summer timetable will not now be feasible before 2011.
The assembly government said the Trunk Road Agency (TRA) was only responsible for the repair to the wall, a section of which collapsed in 2007, to the extent necessary to protect the highway.
A spokesperson said: "WHR have to date submitted invoices to the TRA in the sum of £335,429.74 which on any basis is far greater than the cost of the repairs that the TRA would have carried out."
It said the Agency had paid £73,779.38 to date but WHR were demanding payment of the balance of £261,650.36.
The spokesperson added: "The agency has offered to pay a sum which it considers would have been the reasonable costs of permanent repair to the retaining wall.
"Its offer has unfortunately not been accepted and the parties are continuing to try and resolve matters."
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