The rapid transit system for Belfast that was due to start next year has been delayed until 2018, it has emerged.
Sections of the bus link between the east and west of the city have progressed over the past year, including a new park-and-ride station in Dundonald and bus lanes along two sections of the Newtownards Road.
And earlier this week Whitemountain Quarries was awarded the tender to start work on the Divis Street/Falls Road section.
But the scheme itself will not begin until August 2018, Stormont's regional development committee heard yesterday.
A DRD spokeswoman said budget cuts were to blame for the two-year delay but added that implementation works would continue.
However, Ukip MLA David McNarry called for a more detailed explanation. "The people, businesses and schools around Ballyhackamore will be disappointed to hear that the bus lanes put in place were premature and that they will suffer the consequences," he said.
Mr McNarry also queried how many people in the department knew about the decision to postpone the project until 2018.
"No contract for the operation's provider or the supplier of vehicles has been made, and it appears that crucial areas have not been agreed with Translink," he said.
SDLP MLA John Dallat also called on officials to provide a more detailed explanation.
"The further delay in introducing the system linking east and west Belfast is yet another setback in the pursuit of a modern transport system fit for purpose," he said.
"This announcement, coming amid yet another political crisis, suits those responsible for the mess but who have been left virtually unaccountable by the impending collapse of the Executive.
"The system is a poor substitute for a proper dedicated cross-city rail system, but at the least it was a beginning. Now we need to know when the beginning will be."
A DRD spokeswoman said the potential for a delay had been flagged up last November and blamed severe budgetary pressure for the hold-up.
"It should be stressed that the implementation works are continuing and will provide benefits for existing public transport users in advance of the system becoming operational," she added.
"To date, the following schemes have been completed: the Dundonald park-and-ride site; works on the section of route on the Upper Newtownards Road between Sandown Road and Knock Road, and the introduction of bus lanes on the Upper Newtownards Road between Sandown Road and Knock Road."