And the Government has revealed that the final report of the tribunal is unlikely to be ready before the second half of this year - almost four years after the end of hearings and more than 36 years after the events under investigation.

The bill for the inquiry has now passed £180m, according to information released by the Government.

Costs stood at £181.2m at the end of December, Secretary of State Shaun Woodward said.

Six months earlier, the spending stood at £178,264,000 - an increase of £3m in six months.

More than half of the overall cost is believed to be legal bills for the inquiry.

The inquiry was set up ten years ago to investigate the killing of 14 people by paratroopers in Londonderry in January 1972.

The tribunal began substantive hearings in 2000. The last hearing was held in January 2005.

Recently relatives of the people killed on Bloody Sunday said they expected the final report on the shootings to be complete by May.

But Mr Woodward said Lord Saville, the head of the inquiry, has indicated it is unlikely to be ready in the first half of 2008.

The Secretary of State said "recent media speculation that the report will be concluded in May 2008 has no basis in fact".

"The tribunal are currently engaged in compiling their final report," he said.