Dublin City Council looks set to ban four-axle trucks from the city centre in two years' time.
A new report has found that since the introduction of the HGV ban in February this year, more than 1,500 lorries have been taken off the city's streets every day.
However, the council has had to fork out over €200,000 in rebates to hauliers using the East Link Toll Bridge.
Despite the added cost, the research recommends extending the ban to smaller lorries.