"The marriage will take place next summer," the longtime bachelor, 52, told Nice-Matin for its Thursday morning editions.
Come the nuptials next year, the two will tie the knot in two ceremonies: an intimate civil service inside the Prince's 235-room palace, and a larger, religious one, in Monaco's Notre Dame of the Immaculate Conception Cathedral and which will be televised, sources tell PEOPLE.
Albert, the only son of the late Grace Kelly and Prince Rainer III, and Wittstock, 32, became engaged on Wednesday morning, reportedly in a small garden ceremony at the Prince's palace with only a few family members and friends in attendance. The event will mark the first marriage of a Monaco prince in more than 50 years – since Albert's father wed Hollywood star Kelly in April 1956.
Discussing his future princess with Nice-Matin, Albert cited her history as an athlete, saying, "Sports built her values, and she has a strong personality. Her interest in humanitarian causes, especially those touching children, is an expression of her great sensitivity and openness to others."
Wittstock, he says, "loves Monaco, has a good understanding of it" and "will become involved in its life."
Who Is the Bride-to-Be?Charlene Lynette Wittstock first attracted Albert's attention while winning the 200-meter backstroke at the Monaco International Swim Meet in 2000. "He cracked for her instantly," a friend recalls. The couple dated privately on-and-off for five years before going public at the 2006 Winter Olympics Opening Ceremony in Turin.
Born Feb. 25, l978, in Rhodesia, the name of Zimbabwe at the time of her birth, Wittstock – who stands 5'10" – became naturalized as a South African and began swimming competitively at 16, qualifying as a member of the South African delegation to the 2000 Olympics in Sydney. She effectively retired from competitive swimming in 2005, though in 2007 announced her intention to return to competition.
With support of Albert's sisters, first Caroline (now 53), then, Stephanie (45), Wittstock has undergone a four-year tutelage in Princess 101.
Born Protestant, she has converted to Catholicism and received catechism – conditions imposed by Monaco's Constitution. The former schoolteacher also learned French, Monegasque and European court protocol, developed an interest in fashion (she has a predilection for Armani), and slowly emerged alongside Albert at any number of society functions and balls.
"There's an element of individuality to her,' says royals expert and author Isabelle Rive´e. "Charlene is intelligent, full of character and in many ways her own woman.
Another longtime observer says Wittstock has already begun to assume her place in royal circles. "I saw them last weekend in Stockholm [at the royal wedding of Crown Princess Victoria of Sweden and Prince Daniel Westling, Duke of Vastergotland] and she completely eclipsed him. She's beautiful and so blonde. She looked so princess-like."
Hometown ReactionIn Wittstock's native South Africa, the engagement generated "Local Girl to Marry Prince" front-page headlines, sweeping the country's World Cup elimination to inside pages.
The bride's father Michael Wittstock told the Star that Prince Albert telephoned him on Tuesday afternoon (just prior to the decisive South Africa-France match) to ask his blessing.
"He called me just before kick-off, and I wanted to get the whole thing over and done with," the computer-business operator joked, describing the prince as "a nice chap" and their relationship as being on a "friendly basis."
Speaking to the Citizen, the bride's mother, Lynette Wittstock, a former competitive diver, said she was "thrilled … I am ecstatic my daughter is finally getting hitched. My family is happy, we like him very much."
With additional reporting by KAREN NICKEL ANHALT