LEADING ARTICLE:From Di-vorce to Di-plomacy

With a flash of those lashes, she was off. Dynamic Diana has flown to Buenos Aires, leaving the country breathless behind her, still gossiping, speculating and arguing about that interview. With - of course - impeccable timing, her discussion of the ambassadorial role she hopes to play in future set the scene nicely for her first solo international mission: a trip to Argentina.

We have come a long way from "Gotcha" - the Sun's headline when British troops sank the Argentine ship General Belgrano. Thirteen years after Britain and Argentina went to war over the Falklands, relations between the two countries have gradually been restored through careful diplomacy. Prime Minister John Major and President Carlos Menem met in New York last month. And in September, the two countries signed a joint agreement on oil exploration in the Falkland waters.

The oil agreement exemplifies the realpolitik both countries are now pursuing. Neither government has shifted its official position over the Falklands. Menem has, on several occasions, vowed to recover the islands for Argentina before the year 2000. Rows could have broken out as each country claimed sovereignty over the Falkland waters and the right to levy oil royalties. Instead, the two countries have made an agreement under which both can cash in without abandoning their principles. Britain will continue to hold the Falklands, but Argentina will be essential to the islands' long-term prosperity - not least for the siting of mainland oil installations to make exploration and extraction viable.

The long-term status of the Falklands remains in dispute. Even if military action by Argentina is no longer an option, Menem is bound to use every diplomatic trick available. He is playing a much longer game now to persuade and pressurise the British or the Falkland Islanders that sovereignty should change. The visit of the Princess of Wales will provide him with an opportunity to enhance his credibility in the eyes of the Argentines, Falklanders and British.

It is perfectly legitimate for the Argentine government to pursue its sovereignty claims through legal and diplomatic means. But a member of the British Royal Family must not allow herself to be used and manipulated in the Argentine cause. Being a goodwill ambassador to a country with whom we were at war only 13 years ago requires diplomatic knowledge, skill, tact and political nous - as well as smiles and style.

The visit will be a severe test for Diana's political skills. She has next to no experience of the subtleties of the diplomatic world. On the other hand, she has proved herself to be a consummate operator in her battle with the Royal Family. This could be our chance to find out whether the skills she uses so effectively to promote and position herself can be employed on behalf of her country.