JOHANNESBURG — THE personal rapport between Nelson Mandela and Frederik de Klerk, which is bringing their groups closer together at home, has begun boosting the country's fortunes abroad. The ``red carpet'' treatment accorded President De Klerk in European capitals this week - Paris, Athens, and Lisbon - appears to be due to the success of his first public talks with the African National Congress delegation led by Deputy President Mandela in Cape Town May 2 to 4.
``There is an enormous sense of relief that the two men have found each other,'' said a Western diplomat. ``They will find untold goodwill in the difficult task of delivering their respective constituencies.''
This was acknowledged by Portuguese President Mario Soares when he played host to Mr. De Klerk in Lisbon on Monday - the third stop of a nine-nation tour of Western Europe.
Mr. Soares saluted both De Klerk and Mr. Mandela for getting talks going. He praised De Klerk for his reforms and Mandela for his ``moderation.''
It is the first time in more than four decades - since the days of former Prime Minister Jan Smuts - that a South African leader was given a reception free of diplomatic gestures of disapproval.
Soares said he accepted that the process of reform in South Africa was ``irreversible'' - a term that has become the criterion for lifting economic sanctions and other embargoes on South Africa.
Following a 90-minute meeting with De Klerk Monday, Portuguese Prime Minister An'ibal Cava,co Silva said his country favored lifting all sanctions against South Africa, but within the context of agreements within the European Community (EC).
The Netherlands, one of Europe's most outspoken critics of apartheid, has drafted a plan under which the EC would lift sanctions in six stages. The plan will be debated at the June EC summit in Dublin.
It was after the tentative accord was reached at the Cape Town talks that Mandela subtly paved the way for a review of sanctions. At a joint press conference with De Klerk, he said that the ANC would not renew its call for the escalation of sanctions.
``We hope that - as a result of the agreement we have arrived at, as well as future developments - it will not be necessary for us to call upon the international community to intensify or maintain sanctions,'' Mandela said.
The encounter in Cape Town showed that a warm relationship had developed between Mandela and De Klerk since their first meeting in December last year.
At the joint press conference, each replied separately to most questions, balancing the demands of divergent constituencies. They exchanged jokes on several occasions and shared their impatience with repeated questions to Mandela about whether the ANC would suspend its armed struggle.
Veteran Afrikaner cleric Beyers Naude, a member of the ANC delegation, said that there appeared to be a special chemistry between the two men. ``On both sides of the table, there was unanimous support given to Nelson on the one hand and De Klerk on the other,'' he said.
``If there were differences of opinion, both leaders asked for time - first of all to go and consult with their own constituency. They came back [to their groups after conferring with each other] and said: We have agreed. And everyone accepted that.
``I could not have foreseen the talks taking place without that personal relationship and the building of that sense of integrity,'' the Rev. Mr. Naude said.
Mandela's role in persuading his colleagues to negotiate was acknowledged by South African Communist Party Chief Joe Slovo. ``Mandela told us that De Klerk and his colleagues were people of integrity who meant what they said and that influenced us to come to the table.''
While De Klerk was being feted in Western Europe, Mandela traveled to pay his respects to long-standing African allies - Angola, Nigeria, Algeria, Libya, and Egypt.
Mandela has so far limited his travels in Europe to a visit to Sweden, the ANC's major financial backer, and an unofficial visit to Britain last month to attend a pop concert in his honor.
On June 20, he will travel to the United States for a meeting with President Bush and will address a joint session of Congress. He will then go to London to meet with British Prime Minister Margaret Thatcher. De Klerk is scheduled to meet Mr. Bush on June 18 in Washington.