“Mr. Xi has acquired more power than any Chinese leader since Mao Zedong,” The Economist article states. “It was supposed to let him get things done. What is going wrong?”

John Parker, the Beijing bureau chief of The Economist, said the publication received no warning “that he was aware of” about the website’s being blocked. The Chinese Ministry of Foreign Affairs did contact the publication regarding its cover article but did not discuss blocking the website, he said.

“They expressed their displeasure about the article in question and wanted me to forward their displeasure to the editors in London, which I did,” Mr. Parker said.

In 2001, Time was banned from Chinese newsstands after writing a cover article about Falun Gong, a group outlawed by the Chinese government. That ban was lifted only years later. A Time representative could not immediately be reached for comment.

The Economist has had individual articles blocked in mainland China before, including an August 2015 article about how the Chinese government had reframed historical narratives to justify Mr. Xi’s military ambitions. This is the first time its app has been blocked.

The Chinese government often blocks access to articles or entire websites that contain content it deems unfavorable. Most recently, all mentions of Panama and Panama Papers were blocked on Chinese social media after files leaked from the Panamanian law firm Mossack Fonseca detailing the ownership of offshore shell companies, several of them linked to relatives of high-level Chinese leaders, were published. Chinese editors were instructed to remove any mention of the Panama Papers from their sites.

The New York Times’s English- and Chinese-language sites have been blocked since October 2012, after the newspaper published an exposé on the hidden wealth of the family of former Premier Wen Jiabao. How long The Economist and Time websites will remain blocked is unclear.