Facebook said it was investigating why the #saltbae' hashtag was temporarily blocked on its platform days after a Vietnamese Communist Party official was filmed eating a gold-encrusted steak at the Nusr-Et Steakhouse in London.
To Lam, Vietnam's Security Minister, has faced a barrage of criticism in his home country after a video of him at the Knightsbridge restaurant owned by the Turkish-born celebrity chef Nusret Gokce was circulated on social media.
The tag was blocked worldwide, when a search for the hashtag generated a message saying community standards had been breached, before Facebook made it available once again.
"We've unblocked this hashtag on Facebook and we're investigating why this happened," a representative for Facebook operator Meta said.
Mr Gokce, known to millions of people on social media as Salt Bae, is famed for theatrically seasoning and slicing cuts of meat, which he sells for up to £1,450 ($1,966).
Mr Lam was in the UK as part of the country's delegation for the Cop26 climate change summit.
The incident has left many questioning how such a high-ranking government official allowed himself to be filmed indulging in such expensive food during a Vietnamese clampdown on corruption.
In one Facebook post, Nguyen Lan Thang, who has nearly 150,000 followers, changed his profile picture to a screenshot of the video and pointed out that local media were quiet over the incident.
"Security officers following this account, have you seen the video of minister To Lam eating salt-sprayed beef? Do you know how many months salary you'd have to spend for just one piece of that steak?" Mr Thang wrote online.
Neither Mr Lam nor Vietnam's Foreign Ministry responded to a request for comment.
The original video was removed from Mr Gokce's TikTok account shortly after it was uploaded and further copies were removed from the app for breaching "community standards", Vietnamese TikTok users told Reuters.
"It's not unusual that a government official is super-rich in Vietnam but a minister seen widely opening his mouth to bite a golden steak is shameful," said a customer at one cafe in northern Vietnam who declined to be named, citing safety concerns.
Vietnam is defined as a lower-middle-income country by the World Bank. A minister in the country is paid an official monthly salary of about 16 million dong ($705.47).
The country routinely asks social media companies to censor content it deems to be "anti-state". Last year, Vietnam threatened to shut down Facebook nationwide if it did not remove local political content from its platform.
Facebook declined to comment on whether the Vietnamese government had requested that the latest video be removed.
Vietnam operates one of the largest and most sophisticated online influence networks in South-east Asia.
Mr Lam is one of the most powerful officials in Vietnam, his ministry overseeing both the police and the agencies responsible for suppressing dissent and investigating corruption.
He had been touted as a potential candidate for the presidency in January and has as security minister worked to arrest Vietnamese officials accused of corruption and overt displays of opulence.
Mr Lam last week led a delegation of officials to the grave of Karl Marx in Highgate Cemetery, north London, to "remember the source of the water we drink", the Communist-ruled country's state media reported, citing a Vietnamese proverb about paying respects.
"General To Lam's visit to Karl Marx's grave affirms the Vietnamese people's tradition of 'remembering the source of the water we drink', for the figures who contributed to the direction of a dominated and suppressed nation," a government representative said.