The Great Prince Shan by E. Phillips Oppenheim

That night, Nigel gave a dinner party on Maggie's account at the fashionable London hotel of the moment. Invitations had been sent out by telephone, by hurried notes, in one or two cases were delivered by word of mouth. On the whole, the acceptances, considering the season was in full swing, were a little remarkable. Every one was anxious to come, because, as one of her girl friends put it, no one ever knew what Maggie was going to be up to next. One of the few refusals came from Prince Shan, and even he made use of compromise:

_My dear Lord Dorminster, will you forgive me if in this instance I do not break a custom to which I have perhaps a little too rigidly adhered. The Prime Minister telephoned, a few minutes after we left him, asking me to meet two of his colleagues from the Foreign Office to-night, and I doubt whether our conference will have concluded at the hour you name._