Thomas Bach, International Olympic Committee (IOC) president, plays with a football on the Barra de Tijuca beach in Rio de Janeiro on Aug 4, one year ahead of the start of the Rio 2016 Olympic Games. Xu Zijian for China Daily

The Rio Olympic Games marked a one-year countdown with a samba, bossa nova and carnival celebration and ceremony on Aug 5 as International Olympic Committee president Thomas Bach officially invited the world's athletes to take part in South America's first Olympics.

Since Beijing just won the 2022 Winter Olympics last week, Bach also invited China to attend the ceremony.

"We will come next year. We will come with our friendship, sportsmanship and partnership. We wish our friends good luck. We wish success for the Olympic Games in South America," Chinese Olympic Committee vice-president Yang Shu'an said after accepting Bach's invitation.

Bach also symbolically handed invitations to the representatives of the National Olympic Committees (NOCs) of Greece, Russia, South Korea, Japan, China and Brazil. The NOCs represent the country where the Olympic Games originated, the country of the previous host city and the current Games host cities.

"In exactly one year from now, the eyes of the entire world will be on Brazil," Bach said. "We are confident now that these Olympic Games will amaze the world. The Brazilians will show to the whole world your unique combination of passion and efficiency. "

"This will be the biggest urban redevelopment project since the Barcelona 1992 Olympic Games transformed that city," he said. "The world will talk about a Rio de Janeiro before the Games and a much better Rio de Janeiro after the Games."

In addition to the formal presentation of invitations to the NOCs, the ceremony included a lively selection of songs about Rio performed by well-known local artists. The show took the audience on a musical journey into the heart of samba, showcasing an exclusive selection of hits and giving a special taste of the Rio Carnival.

After suffering from delayed preparation before the 2014 World Cup, Brazil and Rio learned lessons from that. Rio's mayor Eduardo Paes said during a press conference on Aug 5 that all the Olympic preparations are on time and under budget, and Rio will prove Brazil's ability to keep its promises.

"We want to show that we are capable of doing things on time, that Brazil is not a country where everything ends up over budget, everything ends up late," Paes said. "We are literally making a miracle happen here."

Paes said construction work at Barra Olympic Park — the Games' main venue cluster — was 82 percent complete.

The Olympic stadium is at 79 percent complete, the golf course at 98 percent, the athletes' village at 89 percent and the aquatic stadium at 81 percent, according to organizers.

Despite concerns about water quality at the sailing, rowing and canoeing venues, Paes said the Games had prompted a city-wide transformation.

"I'm doing what mayors before me promised but didn't deliver," he said. "Don't come here wanting Swiss, Swedish or Danish levels of development, we are not there – but we have advanced a lot in recent years."

Paes was joined at the press conference by Rio 2016 organizing committee president Carlos Nuzman, who fended off questions about water quality amid reports Guanabara Bay remains strewn with rubbish and sewage.

"We've heard from athletes that have swum with fish, so there are some discrepancies." Nuzman said.

Paes and Nuzman also played down the impact of Brazil's economic malaise, which has coincided with a sprawling corruption scandal at state-run oil company Petrobras.

"At this moment, when all of Brazil is stopped, the city of Rio is forging ahead," Paes said. "Rio City Hall has been doing its homework over the past years."