"Bosnia and Somalia have shown the limits of peace-keeping. They offer a clear lesson. The UN is not yet suited to fight wars," he said in a speech to the General Assembly. "Peace enforcement is perhaps better left to coalitions of the willing acting under UN authority. We must not send in the UN to keep a peace which does not exist, then blame it for failure."
Preventive action was better than a cure, he said, citing the presence of a small UN force in Macedonia to deter fighting and action by the Organisation for Security and Co-operation in Europe to defuse tensions in other countries.
Mr Rifkind urged action to restore UN finances, noting the organisation was owed more than $3.7bn (pounds 2.4bn) in unpaid contributions: "The UN is on the verge of financial collapse."