It is only a matter of time before Sinn Fein joins other Northern Ireland parties in signing up to policing reforms, a senior United States government official claimed today.

President Bush's point man on Northern Ireland, Ambassador Mitchell Reiss, told a police graduation ceremony at Garneville College in east Belfast it was "widely believed" Northern Ireland had one of the best police services in Europe.

Mr. Reiss told graduates that, having come through "considerable reform", the Police Service of Northern Ireland faced more challenges when all sides signed up to policing.

"Given the history of Northern Ireland, your decisions and actions will be scrutinised and constantly weighed. It is a responsibility that you`re more than capable of handling. I know, because I`ve seen your fellow constables rise to this challenge repeatedly."

"And one day soon, you will have to face another challenge. One day soon, all of Northern Ireland`s political parties will move to fully support the PSNI. I believe it is only a question of `when`, not `if`. That`s what I`m working to bring about: that`s what my colleagues in Belfast, London, and Dublin are all working toward. When this happens, you will have to build trust and confidence across the community."

"When this day comes, I know you will meet this challenge, just as you have met so many other challenges that have brought you to this day."

However despite the nationalist SDLP, Irish Government and the Catholic Church backing the police reforms made so far, Sinn Fein claims the reforms have not gone far enough and do not have the support of the majority of nationalists.

The party has been pressing for the transfer of policing and justice powers out of the hands of ministers from Westminster to a devolved government at Stormont.

The British Government is expected to introduce legislation later next month addressing Sinn Fein`s demand.

Sinn Fein met Ambassador Reiss in Belfast earlier today.

Speaking before today's meeting, Sinn Féin President Gerry Adams called on the US to rein in anti-Sinn Féin elements within its system.

Mr Adams said: "If the Bush Administration is to return to the positive role it and the Clinton administration played in the Irish peace process then anti-Sinn Féin elements will have to be reined in."

Sinn Féin had never looked for special treatment, Adams said while acknowledging that 'the bedrock' of Sinn Fein's support came from the US.

"We have never looked for party political support from any US official or agency. All parties have to be given parity of esteem and equality of treatment. Any other approach is counter productive and unhelpful."

Adams said he wanted to see the US administration returning to an even handed and balanced approach.

Ambassador Reiss told an audience which included Chief Constable Sir Hugh Orde and Policing Board member Sam Foster that policing was "the outstanding success story" of Northern Ireland`s peace process.

"Many individuals, including new constables such as yourselves, have taken courageous steps to launch the new beginning to policing," he told the graduates.

"And make no mistake: with sweeping structural reforms, accountability mechanisms, and local oversight, many people think you have one of the best police services in all of Europe. I think everyone in Northern Ireland knows this, as the figures of increasing public support for the PSNI in unionist, nationalist, loyalist and republican communities show."