At a press conference that senior Beijing official Li Fei held here on Monday, journalists were told: questions must be in Mandarin, not Cantonese or English. This was despite the presence of simultaneous interpreters.
In Hong Kong, a city where language is thoroughly politicised, the stipulation was a small but unmistakable show of who's boss.
There was also no coddling of Beijing's hardline decision on Hong Kong's constitutional reform announced a day earlier.
There will be a nominating committee to pre-screen candidates for the chief executive post. The committee's 1,200 members will be drawn from the same sectors as a current panel. Candidates must get at least half their votes. There will be two or three candidates, no more. This effectively means that Hong Kongers will be choosing from a couple of Beijing-anointed candidates.
Setting out such strict rules with little room for negotiation - without even trying very hard to disguise it as something more palatable - shows clearly how the Beijing central government's attitude towards Hong Kong has changed, suggesting that its distrust of the city has only hardened in the 17 years since the July 1, 1997 handover from the British.
Beijing's announcement angered the pro-democracy camp, with the Occupy Central movement vowing to go ahead with its civil disobedience campaign and Hong Kong legislators saying they will scuttle any reform proposals based on the rules.
If so, Hong Kong will be in - as former chief executive Tung Chee Hwa said on Wednesday - for endless "bitter squabbles and paralysis".
Beijing, Mr Li made clear, is prepared to accept this. It has taken into account the consequences of its decision, he added.
So why such a bare-knuckled approach by Beijing, even at a relatively early stage in the Constitutional reform process, prior to a second round of public consultation? The most important factor is Beijing's core strategic interest in Hong Kong, which has been consistent from the 1980s when the late Deng Xiaoping made it clear that getting it back from the clutches of the British is a matter of China's national security and territorial integrity.
Only patriots who "love the country and love Hong Kong" can be in charge, he declared. "They must respect their culture, sincerely support the country's sovereignty over Hong Kong and not undermine its prosperity and stability."
At the same time, Beijing has had an abiding suspicion of the loyalties of certain groups in Hong Kong, especially after the Tiananmen incident in 1989 when large swathes of Hong Kongers actively supported the student activists. Since then, it has accused the city of being a potential base for subversion to undermine the Chinese government, a charge it has made again in recent times.
Several recent developments appeared to have deepened such suspicions, resulting in a tightening grip on the city to pre-empt what Beijing appears to believe to be an oncoming crisis. One is the rise of Occupy Central, which Beijing perceives as a direct challenge to its authority and which thus requires a robust response. The second is the emergence of colonial-era symbols such as the Union Jack touted by fringe groups.