Cars would have to be banned from Dublin's quays to allow a temporary Liffey cycleway, according to council officials.
Many councillors had been demanding action regarding the long-awaited facility which has gone through nine different design proposals since 2011.
The earliest completion date is now 2024, which has been criticised by the Dublin Cycling Campaign.
Councillors at the local authority's February meeting backed the group's demands for a temporary cycleway to be put in place in the meantime.
However Brendan O'Brien, the city council's head of technical services, said the only way this could be done is by banning cars from the quays.
He cited one of the pinch points at the Ha'penny Bridge, where there is only two traffic lanes.
Mr O'Brien said public transport had to allowed, so the only option with a temporary cycleway would be to ban cars.
He said this would cause problems such as deliveries and access.
The solution proposed is to build boardwalks for pedestrians at certain sections.
He said the quay walls are being assessed architecturally, environmentally and archaeologically to see if this can be done as a lot of consultation and permissions are needed.
Mr O'Brien said he would come back to the March meeting with plans to show where the cycle track could be put in easily and where difficulties lie.
The latest plan involves segregated cycle tracks either side of the Liffey each covering 5km from Heuston Station to the port.