Hong Kong authorities barred high-profile pro-democracy activist Joshua Wong from an election, and the city's leader ruled out political solutions before the end of the violent protests gripping the semi-autonomous Chinese territory.

The developments Tuesday were likely to further widen divisions in Hong Kong, which has been wracked by more than four months of unrest driven in part by demands for political reform. Hong Kong's leader, Carrie Lam, also warned that the Asian financial hub was on the brink of an economic recession.

A returning officer notified Wong his nomination as a candidate in next month's elections was ruled invalid, according to a copy of the letter Wong posted on his Twitter account .

"The decision to ban me from running for office is clearly politically driven," Wong told reporters. He said Beijing was pressuring Hong Kong election officials to carry out political screening but it would backfire.

"It will just trigger more and more Hong Kongers to take to the street and also vote in the election."

Wong, 23, became known as the young face of Hong Kong's "Umbrella Movement" that peacefully occupied streets for 79 days in 2014, and he has since been repeatedly arrested and jailed. He has been less important to the current protest movement, which has been leaderless and whose participants have sought to remain anonymous.

His activities have nonetheless made him a target of China's communist leaders, who have used him to accuse foreign powers of colluding with anti-China separatists to foment unrest.

The government confirmed Wong's disqualification, without identifying him.

The returning officer said in the letter that Wong's embrace of the concept of self-determination includes Hong Kong's independence, which goes against a requirement to promise to uphold its constitution. But Wong denied that, saying his answers to the officer's questions were twisted.

Wong and other pro-democracy activists were disqualified from running in previous elections. But the others have been approved for the Nov. 24 local district council elections, making him the only one to be banned.

Neighbourhood councillors and half of Hong Kong's legislature are directly elected, but the rest are chosen by trade and industry groups while the top leader is handpicked by an elite pro-Beijing panel. The protesters' demands include full democracy.

The disqualification came as Lam ruled out finding a political resolution before ending protest violence.

Hong Kong's Chief Executive Carrie LamLa says city is at risk of falling into a recession as it enters its fifth month of protests, which has punished the city's tourism and retail industries. (Jorge Silva/Reuters)

"For the government to resort to measures that will appease the violent rioters, I don't think that is the solution," she told reporters.

"Until and unless we tackle the violence and put an end to it, it is very difficult to continue the political dialogue we have done," Lam said.

On Twitter, Speaker of the House Nancy Pelosi called the action against Wong "another blow against rule of law in Hong Kong and the principle of 'One Country, Two Systems.'"

"The people of #HongKong should be able to choose their elected officials," wrote Pelosi, who this month backed legislation that would tighten U.S. scrutiny of Chinese rule in Hong Kong.

Singling out and banning <a href="https://twitter.com/joshuawongcf?ref_src=twsrc%5Etfw">@joshuawongcf</a> from running in the upcoming District Council election is another blow against rule of law in Hong Kong and the principle of “One Country, Two Systems.”<br><br>The people of <a href="https://twitter.com/hashtag/HongKong?src=hash&ref_src=twsrc%5Etfw">#HongKong</a> should be able to choose their elected officials. —@SpeakerPelosi

The U.S. State Department did not immediately respond to requests for comment.

Hong Kong has been gripped since early June by the political crisis, with peaceful but often unauthorized marches descending into chaos as hardcore demonstrators hurling fire bombs and bricks battle police firing tear gas, rubber bullets and water cannon. Both sides blame each other for using increasingly aggressive tactics.

Lam said the city is at risk of falling into a recession as it enters its fifth month of protests, which has punished the city's tourism and retail industries.

"If this quarter's growth rate, compared to the second quarter's growth rate, is negative, it will be the second decline in a row. Then it can be said that we have entered a technical recession," she said, adding that the economy could end up contracting for the year as a whole.