London: Britain's High Court on Thursday decided that the Serious Fraud Office should be allowed to go to the highest court of appeal over a ruling that it acted unlawfully when it abandoned a corruption inquiry involving a lucrative arms deal with Saudi Arabia.

It will now be up to the House of Lords - the top appeal court - to decide whether the judiciary has the right to intervene and force the government to reopen the sensitive inquiry, which was suspended when Tony Blair was premier.

Lord Justice Moses, who ordered the Serious Fraud Office to pay all court costs, said the case has raised crucial questions that can best be resolved by the House of Lords.

He said that Saudi officials had made an explicit "drop it or else" threat in an effort to block the bribery investigation.

"That has raised a big question on what should be the public response when a threat is issued by someone outside the control of the court and outside the jurisdiction of the United Kingdom," he said. "This is a paradigm case that goes to the way this country is governed and to its constitutional principles." He said the Saudis had "access to Number 10 Downing St." when they made the threat, which involved an end to Saudi cooperation in Britain's global anti-terrorism campaign.

A spokesman for the Serious Fraud Office said after the ruling that the investigation will not be reopened until the House of Lords has ruled. That may take several months or longer.

The High Court decision - which authorises an appeal of its own ruling two weeks ago that halting the inquiry was unlawful - drew immediate praise from Richard Stein, a lawyer representing two public interest groups that successfully challenged the Serious Fraud Office's decision to drop the inquiry.

"This just confirms that the justices think it's very important," he said. "This whole case gives us a feeling that the court can stand up for the rule of law in cases of sleaze and dodgy behaviour, and we're glad that somebody can."