Ending the arms embargo on China would "send the wrong signal" about human rights abuses, MPs have said.
Paramilitary policeman with water-cannon at Tiananmen Square
A Commons committee said the Chinese should first give "strong undertakings" to address human rights concerns before any change of policy is implemented.
The European Union is considering lifting the censure, imposed after the Tiananmen Square protests in 1989.
Meanwhile more than 500 Chinese human rights activists have sent a letter to the EU appealing for the ban to stay.
It says the rights situation has not undergone any fundamental changes in the past 16 years.
The arms embargo was expected to be replaced with a code of conduct governing all EU arms exports.
But the Commons' Foreign Affairs committee said: "The raising of the EU arms embargo on China would send the wrong signal at this time, in the absence of strong undertakings from the Chinese government to address human rights issues."
A group which draws together MPs from four Commons select committees concerned with arms sales on Wednesday also raised concerns about lifting the embargo.
It said such a move threatened "major EU-US trade repercussions".
There was also a risk "EU member states enhance China's military capacity in a worrying way" and arms exported from Europe could be used for internal repression.
The United States is vehemently opposed to lifting the embargo and EU support now appears to be crumbling.
Washington says China has not made sufficient progress on human rights to warrant a lifting of the embargo.
President Bush is also concerned that ending it would change the balance of relations between China and Taiwan.
Because the US might help defend Taiwan in the event of an attack by China, Washington does not want anything to add to Chinese capability.
There are fears if the arms embargo was lifted the US could retaliate by refusing to buy arms from EU countries.