Political pressure is growing here for the Hong Kong government to protect Edward Snowden, who has said he will remain in the city and allow the people here to “decide his fate.”

Yet Snowden is depending on a place that isn’t in control of even its own destiny.

Hong Kong has a separate legal system from mainland China and an avowed devotion to free speech, but the city ultimately answers to Chinese leaders in Beijing, who may be wary of a confrontation with the U.S. government.

“Even we cannot decide our own fate,” said Jerry Chan, 26, at a rally Saturday near the U.S. Consulate to support Snowden.

Sixteen years after its transfer from British to Chinese rule, Hong Kong remains a massive experiment in whether former Chinese leader Deng Xiaoping’s idea of “one country, two systems” can work. And the surprise arrival of an American bearing information about a secret U.S. surveillance program could test the already uneasy relationship between Beijing and Hong Kong.

The chief executive of Hong Kong, Leung Chun-ying, made his first public comments Saturday about the case, saying the Hong Kong government would follow existing laws if and when the U.S. government requested help dealing with Snowden.

“When the relevant mechanism is activated, the Hong Kong [Special Administrative Region] Government will handle the case of Mr. Snowden in accordance with the laws and established procedures of Hong Kong,” Leung said in a statement. “Meanwhile, the government will follow up on any incidents related to the privacy or other rights of the institutions or people in Hong Kong being violated.”

The first step in the extradition process, once the U.S. government makes a formal request for Hong Kong’s assistance, will be for Leung to decide how to proceed based on the extradition treaty between the two countries. Leung, who is widely viewed to be pro-Beijing, was selected by a small committee last year and has struggled to win popular support. In January, thousands of protesters called for his resignation.

“We call our so-called chief executive a puppet of Beijing,” said Kris Cheng, 24, at the Snowden rally. “So in national security or defense issues, he has to listen to Beijing.”

A poll by the South China Morning Post showed that one in two Hong Kong residents thinks the government should not give up Snowden if the U.S. government requests an extradition.

The protest in Hong Kong on Saturday afternoon drew between 200 and 300 people amid steady rainfall.

“Protect freedom! Defend Snowden!” shouted protesters in Cantonese as they walked toward the U.S. Consulate in the central district of Hong Kong, with a few holding up pictures of Snowden.

If political pressure continues to rise, the situation could become complicated for China’s leaders. Agree to extradition, and they risk creating the impression of interfering with Hong Kong’s legal process. Resist helping the U.S. government apprehend Snowden, and Beijing could hurt recent efforts to improve relations between the two countries.

The Chinese government may also be wary of stepping into any controversy related to government surveillance, given the vastness of its own security apparatus.

Despite its transfer to Chinese rule in 1997, there remains a gulf between Hong Kong and China, with resentment building from Hong Kong residents toward the increasing number of visitors from the mainland.

The border is marked by a barbed-wire fence that snakes along the Shenzhen River at the northernmost part of Hong Kong in the area known as the New Territories. Security here is so stringent that even entrance to neighborhoods in Hong Kong very close to the border is often restricted.

On a recent day at Lo Wu, one of the busiest border crossings in the world, there were teeming crowds of mainland visitors carrying bulk purchases back across the border to Shenzhen, the booming city just on the other side of the border from Hong Kong.

Chinese nationals require permits in order to enter Hong Kong, where they frequently shop for everything from diapers to iPhones, often because prices are better or because Hong Kong has a better selection of things to purchase.

Hong Kong residents, for their part, often view the mainland visitors as outsiders who cause problems, for instance driving up real estate prices with their widespread home purchases or even taking up too many hospital beds with pregnant women who wish to have their children born in the semiautonomous city. A recent survey showed only 16.6 percent of Hong Kong residents view themselves first as being Chinese citizens.

“It is a special [administrative] region of China, but Hong Kong people like to put the emphasis on ‘special,’ ” said Zhang Junyi, an expert on Hong Kong history at the Chinese Academy of Social Science. “They believe they are different from mainland China.”

Liu Liu and Ricky Li contributed to this report from Beijing.