"All-out efforts should be made to improve people's livelihood and maintain social stability."
Separately on Monday, Meng Jianzhu, another minister in the public security ministry, spoke of "lots of social problems affecting stability under the current circumstances", according to a Xinhua report.
Jianzhu "urged local officials to be sober-minded and fully realise the importance and urgency of safeguarding social stability".
String of incidents
The taxi drivers' clash with police in Guangzhou on Monday came during a protest against the alleged beating of a driver by an official.
The violence was the latest in a string of recent incidents, including strikes by taxi drivers, protests by laid-off workers and a riot involving thousands of people over a government resettlement plan, and comes as China's export-driven growth slows and companies shed staff.
The taxi drivers were shown scuffling with police on Hong Kong's Cable TV during a march to protest against the weekend beating of a taxi driver by three drunken men, one of whom claimed to be a city official, according to local media reports.
The authorities denied any of the attackers were officials and detained the three who had beaten the driver. Television images also showed some protesters being dragged by police to waiting vehicles.
Wu Sha, the head of Guangzhou's public security bureau, urged the drivers to remain calm and pledged to resolve the matter in accordance with the law.
Xinhua said the protesters had dispersed by noon on Monday.
Protests and incidents of unrest have risen in China in recent weeks, with mass factory closures and protests by newly laid-off workers in Guangdong province, riots in northwestern Gansu province and a mass petition in Beijing.
Residents said heavy-handed methods employed by government forces, including the use of tear gas to disperse protesters, fan public anger and exacerbate the riots.
The World Bank said on Tuesday that China's downturn should worsen in the first half of 2009 as the global crisis hits it in earnest and exports weaken.
The Bank said that Beijing's $600bn stimulus plan announced this month should help to offset sharp declines in global and domestic demand.