Japan's Hidenari Kanayama races during a luge training session at the Sanki Sliding Center in Rosa Khutor, the venue for the 10 Alpine skiing medal events, near Sochi on Friday. Photo: AFP

Two topless Femen activists demonstrate in front of the Russian Embassy in Berlin on Friday. Femen staged the protest on the opening day of the Olympic Games in Sochi to demonstrate against Russian President Vladimir Putin's "dictatorship and oppression of human rights in Russia." Photo: AFP

Russia on Friday officially kicked off the 22nd Winter Games in the Black Sea resort of Sochi, deemed a capstone of the country's revival more than two decades after the collapse of the Soviet Union.

At press time, the opening ceremony had just started in the 40,000-seat Fisht stadium.

Details have been kept under wraps but the head of the Sochi organizing committee Dmitry Chernyshenko said the ceremony "will be one of the most exciting and visual ever."

Some of Russia's most decorated cosmonauts will raise the Russian flag to the top of the stadium, AFP reported.

Russian President Vladimir Putin, who has spearheaded the Sochi Games from the bid victory in 2007, was joined by more than 40 other heads of state and leaders at the ceremony.

Dignitaries included Chinese President Xi Jinping, UN Secretary-General Ban Ki-moon, Japanese Prime Minister Shinzo Abe, Turkish Prime Minister Recep Tayyip Erdogan and Ukrainian President Viktor Yanukovych, who is facing a political standoff at home.

The absence of US President Barack Obama and a host of key EU leaders was seen by some as a snub to Russia after it passed a law banning the dissemination of gay propaganda to minors.

In a symbolic gesture, Google marked the Winter Games by flying the gay flag Thursday on a search page Doodle that linked to a call for equality in the Olympic Charter.

In addition to the no show of Western leaders, the Sochi Games are also caught up in security concerns as separatist guerrillas seeking an independent Islamic state in Chechnya and neighboring regions of southern Russia have vowed to disrupt the Games.

The US on Thursday announced a temporary ban on liquids and gels in hand luggage on Russia-bound flights, following a warning that militants could stuff explosives into toothpaste.

Reuters on Thursday quoted US and European officials as saying that attacks by militants during the Games are highly likely, but will probably be aimed at "softer" targets elsewhere in Russia, such as public transportation or other civilian venues.

About 37,000 security personnel are on high alert as Putin vowed a "ring of steel" around the sports venues.

With an estimated price tag of $50 billion for building facilities and infrastructure in the underdeveloped southern Russian region, the Games are the most expensive ever.

"From the beginning of our Olympic journey, legacy was our guide," Chernyshenko on Thursday told International Olympic Committee (IOC) members in his final progress report. "The Olympic Games were the catalyst we used to speed up the renovation of this most beautiful part of Russia, which needed it since the middle of the last century."

Residents have shown mixed feelings toward the infrastructure development over the last seven years, which they said has made Sochi "the largest construction site in Europe."

Some complained about "chaotic scenes," pollution and traffic jams caused by the construction, while others told the Global Times the Games have transformed the city.

Lev Belousov, rector of the Russian International Olympic University, told the Global Times that Sochi could compete with any ski resort in Europe. "The Games could also help boost Russian economy and elevate Moscow's global image," he said.

The Games have attracted visitors from both Russia and other European countries, he said, and the venues could be used for hosting the 2018 World Cup.

"The legacy can't be weighed only by money. The Games can also bring cultural and spiritual legacies, strengthening national cohesion and raising Russia's international status," he said.

Nearly 3,000 athletes from 87 countries and regions will compete for 98 gold medals in 15 disciplines across seven sports. China this year sent a 139-member delegation including 66 athletes.

A powerhouse in the Summer Games, China is weak at winter sports. The absence of star skaters Wang Meng and Yu Jing, who had to withdraw from the Games with injuries, has made it more difficult for China to repeat its successes at the 2010 Vancouver Winter Games.

Infostrada Sports, a Netherlands-based sports and media company, projected China will rank 10th on the medal table, with four golds, two silvers and seven bronzes. It also projected the US will top the table, with host Russia finishing fifth.

President Xi on Friday visited the Chinese delegation and encouraged athletes to surpass their limits during competition.

On the previous day, Xi met IOC President Thomas Bach. At the meeting Xi noted Beijing is joining hands with neighboring city Zhangjiakou to bid for the Winter Games in 2022.

The bid will promote winter sports among the Chinese people and carry forward the Olympic spirit, he said.

Agencies contributed to this story