In his response to a discussion paper crafted under Committee of the Whole chairman Philippe Kirsch's guidance this week, Scheffer said Washington is willing to compromise on UN Security Council oversight of an ICC, a stance many rights groups had sought.

The United States, however, is also adopting a considerably harder line on the question of states' consent to the ICC than many delegations had expected. Combined with its continuing opposition to a 'proprio motu' ICC prosecutor empowered to initiate investigations independently, that stance could leave the Court largely ineffective even without an explicit Security Council veto, some non-governmental organisations (NGOs) argue.

A particular worry is that Scheffer argued that the only crime over which the ICC should have automatic jurisdiction is that of genocide, while Washington rejected such jurisdiction over either crimes against humanity or war crimes.

"We have long believed that an effective ICC must recognise the realities of state practise and the potential for near-universal state participation provided the Court does not straightjacket states at its inception into an all-or-nothing acceptance of jurisdiction," Scheffer told delegates.

"Automatic jurisdiction over all the core crimes might satisfy the most optimistic requirements of theory, but it is a recipe for limited participation in the Court, and, in the result, an ineffective Court,"  Scheffer said.

Jelena Pejic, senior programme officer for the Lawyers Committee for Human Rights, countered that all three core crimes are "all of equal gravity" and should therefore be subject to the same guidelines or jurisdiction.

Of the three, she argued, war crimes is the only one over which inherent jurisdiction has previously been established by "black-letter law", since nations were instructed to comply with investigations of "grave breaches" of the 1949 Geneva Conventions.

In addition, Scheffer emphasised that the United States prefers to require "the prior consent of the state of nationality of the accused" for all states which are not party to the ICC statute and rejects all alternatives which it contends "incorporate a form of universal jurisdiction".

Those two positions, Pejic warned, may make it difficult to obtain consent for ICC jurisdiction in cases that are not referred to the Court by the Security Council.

Ironically enough, those problems arise at a time when Washington has garnered qualified praise from the 60-odd "like-minded" group of nations for trying to find compromises on Security Council oversight and other key issues. As one like-minded delegate put it, "Nobody should believe that we do not respect the work of the United States and France, and the untiring efforts by Ambassador Scheffer" to secure a compromise deal.

But in many respects, the compromise that is emerging is one that favours the United States, France and other countries which have in general been wary of creating a Court that is either too powerful or too independent of the Security Council.

On Wednesday, many like-minded nations, worried that time in the ICC conference is running out, signalled their willingness to drop demands that the ICC investigate a wide range of crimes, including terrorism, drug trafficking, the use of nuclear weapons and blockades - all items whose inclusion Washington resisted.

During intense negotiations this week, signs have also emerged that nations would only add the crime of aggression to the ICC statute if it is tightly defined and its commission is determined by the 15-nation Security Council; otherwise, some nations which had supported including aggression fear there may be no agreed definition for the crime before the end of next week.

Three of the Council's five permanent members - the United States, France and Russia - have now also thrown their weight behind options which would require the consent of state parties to the ICC statute to investigate war crimes or crimes against humanity. Such consent requirements, one delegation warned, would make the ICC an "a la carte Court" where nations could pick and choose when they want to accept its jurisdiction.

The tough line by Washington on such issues has been counterbalanced by its hinting that the 'Singapore compromise', in which the Security Council could remove cases from ICC consideration for 12-month periods but would not oversee the Court's entire docket, could be acceptable.

"We are willing to work with others to seek a compromise with respect to the Council's proper role, but it cannot be one which seeks to rewrite the powers and functions of the Security Council," Scheffer said Thursday. "For example, we need to find wording that does not impose an obligation on the Security Council to draft its own resolution with a specified time period for its applicability."

That position represents an advance which many human rights groups have long desired, but it may not be a sufficient one in light of the other US positions.. "Acceptance of the Singapore proposal...is just one step that delegations have made toward an effective Court," Pejic said. But she added that on its own, that compromise would not be enough for the Court to be a strong one.