China's Communist Party leader, Jiang Zemin, has urged the country's judicial authorities to crush any attempt to undermine political stability.

Addressing a law enforcement conference broadcast on national television news, he said any attempt to undermine national security must be nipped in the bud.

In a speech peppered with references to hostile forces abroad and dissatisfaction among laid-off workers at home, Jiang Zemin warned that the 50th anniversary of Communist Party rule and the return to China of the Portuguese colony of Macao would make 1999 a vital year for China. Preserving stability was paramount, he said.

Publishers warned

Jiang Zemin: 'Preserving stability is paramount'

The People's Daily newspaper also chimed in with a warning to publishers that they would in future be held responsible for any subversive material appearing in their publications and charged accordingly with attempting to overthrow the state.

After the prison sentences handed down earlier this week to three veteran dissidents - between 11 and 13 years each - no one will take such threats lightly. An intellectual community, which only a few months ago had been emboldened by an apparent relaxation in the political mood, is now likely to return to mouthing the Communist Party's slogans.

Appeal to UN

But defiance is not entirely dead. On Wednesday four intellectuals sent a letter to the UN Secretary-General, Kofi Annan, appealing for international pressure on Beijing.

Western governments have already protested over the dissident trials. For British Prime Minister Tony Blair, and the United States President, Bill Clinton, these events were a double disappointment.

Both leaders visited China earlier this year, and argued that a softly-softly approach to the human rights dialogue with Beijing was the best strategy. They pointed to China's signing of the UN Covenant on Civil and Political Rights as a sign of progress.