The main opposition Conservative Party insisted on Thursday the government must clarify how Attorney General Lord Goldsmith reached his verdict, to remove suspicions that he had come under political pressure.

"What happened to enable him to alter his position?" asked Conservative legal spokesman Dominic Grieve in a heated House of Commons debate. "Does the foreign secretary not realise how corrosive this entire episode now is to trust in government."

Blair's government repeatedly has declined to publish Goldsmith's advice in full. Foreign Secretary Jack Straw told lawmakers on Thursday that the attorney general reached his view independently and accused the Conservatives of trying to score political points.

The fallout from the war in Iraq continues to trouble the government. With elections expected in early May and public trust in Blair's judgment eroded, the ongoing saga about the legality of the war is inconvenient and potentially damaging.