The High Court in Belfast has overturned a decision by the North's Department of the Environment to grant planning permission for the development of the Belfast Harbour estate.

Yesterday's ruling by Lord Justice Kerr came as a victory for Belfast City Council and the Belfast Chamber of Trade who had challenged the previous DoE decision on the grounds that a new retail development at the D5 site at Tillysburn would seriously damage businesses in the Holywood, Connswater and Dundonald areas of east Belfast.

The High Court ruled that the Northern Ireland Environment Minister Lord Dubs did "not have the full facts" when he granted the planning permission. According to the developers, the planned £65 million shopping complex could have created up to 1,200 new jobs and would have accommodated retailers such as Sainsbury's supermarkets and a B&Q superstore.

However, traders in the area were worried about the effects of the complex on their businesses and lobbied Belfast City Council over the plans.

The Chamber of Trade's chief executive, Mr Frank Caddy described the High Court ruling as a "landmark victory".

He added: "We are delighted that our judgement that planning regulations were broken both in letter and in spirit has been vindicated."

The SDLP environment spokesman, Mr Eddie McGrady called for an immediate inquiry into the decision-making process at the DoE which had led to the granting of the original planning permission.

A spokeswoman for the DoE said the department was "carefully considering the High Court decision with its legal advisers" and could not comment at this stage.