RIO DE JANEIRO—Rio Mayor Eduardo Paes took a victory lap Tuesday, hailing the 2016 Olympics as a success, while guaranteeing government support for the city's upcoming Paralympic Games, amid disappointing ticket sales and weak sponsorship.

Only 20% of the 2.5 million tickets for the Paralympics, which run from Sept. 7 to Sept. 18, have been sold. The event's financing remains tenuous as organizers continue to seek additional sponsors and revenue from last-minute ticket sales.

Rio's local government and Brazil's federal government have pledged a combined 250 million reais ($77 million) to bail out the Rio 2016 organizing committee, which says it is short on cash to run the Paralympics. The committee has declined to open its books, and recently won a court battle to keep its finances private.

At a Tuesday press conference in Rio, Eliseu Padilha, chief of staff for Brazil's acting President Michel Temer, reiterated that government backing for the Paralympics is assured if more private sponsorship can't be found to bridge the funding gap.

"The financial question has been resolved," Mr. Padilha said. "There will be a lot of people, and I'm not worried at all. It will be a great success."

Mr. Paes, who appeared with Mr. Padilha, also gave assurances that the Paralympics will go on.

"We will give the resources, if necessary," Mr. Paes said. "We will make the Paralympic Games incredible."

Even with the promise of taxpayer-funded help, the International Paralympic Committee is bracing for cuts that are "likely to impact nearly every stakeholder attending the Games," Philip Craven, the committee's president, said last week. IPC officials said transportation, media facilities and spectator services are likely to be affected.

Rio on Sunday closed the Olympic Games, which were hailed as an operational success despite a steady stream of glitches, including long lines, vanishing volunteers and a diving pool that mysteriously turned green. Sporting victories, including Brazilian gold medals in soccer and volleyball—the country's two most popular sports—toward the end of the Games helped the hosts finish on an upbeat note.

Critics have decried the $12.7 billion price tag and said the money could have been better spent. Before the Games, the state of Rio de Janeiro was forced to declare a "state of public calamity" and received a federal government bailout.

Mr. Paes on Tuesday defended the Games, whose legacy projects include a new subway extension, a spruced-up port area and miles of additional bus rapid-transit lanes.

"The Games were never about making Rio a perfect place," Mr. Paes said. "I would say we would do everything again because we have become a better city."

Worries about Brazil's Zika virus epidemic had led to calls by some health experts to reschedule the Games. Mr. Paes said city health officials had not registered a single case of Zika among more than 8,000 people treated during the Olympics. He said 95% of visitors interviewed would like to return to Rio, according to survey carried out by the municipality.

Local service industries on Tuesday said they enjoyed a boost during the Olympics, with hotels at 94% occupancy, according to the Brazilian Hotel Industry Association of Rio de Janeiro.

Airbnb said more than 85,000 people booked accommodations through the company in Rio during the Games but demand for the Paralympics remains weak.

"We haven't seen (so far) the strong pickup we saw during the Olympics," said Leonardo Tristã o, Airbnb's general director in Brazil.

Rio hotels haven't released official numbers but recently estimated that less than 50% of hotel rooms in the city have been booked for the Paralympics.

Rio's Paralympic ticket sales are increasing but remain well below London's in 2012, with a record of 2.7 million seats sold. So far, 500,000 tickets have been bought of 2.5 million put on sale for Rio's Paralympics.

Weak ticket sales and a lack of sponsorship funds led the Rio 2016 local organizing committee to seek a taxpayer bailout. An injunction prohibiting any public money from flowing to the committee unless it opened its books was overturned last week. The city of Rio has agreed to contribute 150 million reais if needed, with another 100 million promised by the federal government.

The shaky funding has led to a delay in local organizers paying travel grants to foreign delegations to transport athletes and their coaches to Rio. Mr. Craven of the IPC said last week that "around 10" national delegations were uncertain whether they would be able to make the trip. He declined to state which ones.

A Rio 2016 spokesman on Tuesday didn't confirm whether the travel grants had been paid.

Write to Luciana Magalhaes at Luciana.Magalhaes@wsj.com

(END) Dow Jones Newswires

August 23, 2016 20:35 ET (00:35 GMT)

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