BELFAST, Northern Ireland - Pressing ahead with divisive plans for reforming Northern Ireland's predominantly Protestant police, Britain appealed Friday for Protestants to accept the need for painful changes and for Catholics to give the new force a chance to succeed.
Northern Ireland Secretary Peter Mandelson issued his appeal a day after U.S. congressmen supportive of Irish Catholic demands criticized Britain's approach to police reform as too slow and too cautious.
Mandelson also published guidelines for flying the British flag over government buildings in Northern Ireland, another issue dividing the province's Protestant-Catholic administration.
Since the coalition Cabinet took shape in December under terms of a 1998 peace accord, the IRA-linked Sinn Fein party has outraged Protestants by ordering that British flags not be flown at the two government departments under its stewardship.
Sinn Fein said it would fly the British flag only alongside the tricolor of the neighboring Republic of Ireland, which dropped its constitutional claim to the province as part of the 1998 pact.
The Cabinet failed to agree on a flags policy. Mandelson's draft proposal calls for the British flag to be flown over government buildings on 17 days each year, including the birthdays of British royalty and St. Patrick's Day.
He gave local politicians until Oct. 20 to respond to the plan. Sinn Fein spokesman Alex Maskey said it was designed to placate Protestant concerns ''against the spirit of the Good Friday agreement.''
Later in a speech at Oxford University, Mandelson insisted his plans for reshaping the Royal Ulster Constabulary into a new mixed-religion Police Service of Northern Ireland met ''the letter and the spirit'' of a blueprint for police reform produced last September under terms of the accord.
Like the flags issue, debate over the future of the RUC has split the coalition. Its senior Catholic and Protestant ministers, Seamus Mallon and David Trimble, plan to plead their cases to President Clinton in Washington on Wednesday.
Many within Trimble's Ulster Unionists, the largest Protestant party, want to withdraw from the government - forcing its suspension for a second time - unless Britain retains the RUC name.
Trimble, at the same Oxford gathering of British and Irish lawmakers, welcomed Mandelson's flag plan, saying it recognized Northern Ireland's place within the United Kingdom. ''I sometimes wonder whether Sinn Fein understands the agreement,'' he added.
But Trimble, criticizing the police plan, suggested it was designed to provide Irish Republican Army supporters ''a symbolic victory over the RUC.'' He said the renaming issue ''continues to threaten the survival of the agreement.''
Mandelson said Britain's goal is to see the police, currently 8 percent Catholic, become 30 percent Catholic within a decade. The RUC name sounded too partisan in favor of Protestant tastes and would have to go, he said.
''I fully recognize the genuine pain that causes many unionists,'' Mandelson said. ''I do not pretend otherwise. But, equally, I have to recognize the hard fact that the name RUC deters many (Irish) nationalists from joining the police service.''
Mandelson said police reform legislation due for passage in October would stress that the RUC was being incorporated into the new Police Service, not disbanded in line with IRA demands. The outlawed group killed nearly 300 officers before calling a 1997 cease-fire.
Catholics must respect ''the link between the old and the new services, because this is as essential to unionist confidence as a change of name is to nationalist confidence,'' Mandelson said.
He emphasized that a new force with Protestants and Catholics working more easily together would ''evolve as new attitudes are bred, as past distrust fades and old animosities die down.''
But this would happen, he said, only if traditionally hostile Catholics gave the Police Service ''the chance to succeed. It cannot be produced like a rabbit out of a hat. It will quickly find its feet - but not if it is written off before it is given the chance to walk.''