The official inquiry into the events surrounding the demise of MG Rover two years ago has so far cost the taxpayer almost £8.4m - more than the emergency loan granted by the government to pay workers' wages in the immediate aftermath of the company's collapse.

The Department of Trade and Industry, which appointed the inspectors and which is funding their work, said the costs of the inquiry, up to the end of March this year, amounted to £6.78m plus £1.24m in VAT and almost £350,000 in "disbursements".

The inspectors were appointed at the end of May 2005 with wide-ranging powers, under the Companies Act, to investigate the events which saw MG Rover forced to call in the administrators, the subsequent closure of its Longbridge plant and the loss of more than 6,000 jobs. The then trade and industry secretary, Alan Johnson, said in 2005 that he wanted the inspectors - insolvency law specialist Guy Newey QC and Gervase MacGregor, a specialist in accounting fraud - to report "as quickly as possible".

Yesterday a DTI spokesman said the inquiry was continuing. "The DTI and the inspectors are intent on completing this inspection as quickly as possible, with due regard to the fairness of procedures, and the thoroughness of the task."

Many of the assets of MG Rover and its sister company, Powertrain, were bought by the Chinese car maker, Nanjing Automobile Corporation, after a bidding war with the rival Chinese carmaker, Shanghai Automotive Industry Corporation (SAIC), the company with which Rover had sought, unsuccessfully, to strike an alliance which it hoped would have kept it in business.

Many of the assets were moved to China where NAC has now begun manufacturing the MG TF sports car and the MG ZT saloon. The company also took a long lease on part of the Longbridge plant. Yesterday NAC UK announced the Longbridge plant in the West Midlands would reopen later this month with a ceremony which will see pre-production models of the MG TF driven off new production lines.