HONG KONG/BEIJING, June 30 (Reuters) - Chinas parliament passed national security legislation for Hong Kong on Tuesday, setting the stage for the most radical changes to the former British colonys way of life since it returned to Chinese rule 23 years ago.

State media is expected to publish details of the law - which comes in response to last years often-violent pro-democracy protests in the city and aims to tackle subversion, terrorism, separatism and collusion with foreign forces - later on Tuesday.

Amid fears the legislation will crush the global financial hubs freedoms, and reports that the heaviest penalty under it would be life imprisonment, pro-democracy activist Joshua Wongs Demosisto group said it would dissolve.

It marks the end of Hong Kong that the world knew before, Wong said on Twitter.

The legislation pushes Beijing further along a collision course with the United States, Britain and other Western governments, which have said it erodes the high degree of autonomy the city was granted at its July 1, 1997, handover.

The United States, already in dispute with China over trade, the South China Sea and the novel coronavirus, began eliminating Hong Kongs special status under U.S. law on Monday, halting defence exports and restricting access to high-technology.

China said it would retaliate.

Hong Kong leader Carrie Lam, speaking at her weekly news conference, said it was not appropriate for her to comment on the legislation as the meeting in Beijing was still going on, but she threw a jibe at the United States.

No sort of sanctioning action will ever scare us, Lam said.

Lau Siu-kai, vice-president of a think-tank under the Beijing cabinets Hong Kong and Macau Affairs Office, told Reuters the law was passed unanimously with 162 votes. It is expected to come into force imminently.

The editor-in-chief of the Global Times, a tabloid published by the Peoples Daily, the official newspaper of Chinas ruling Communist Party, said on Twitter the heaviest penalty under the law was life imprisonment, without providing details.

Authorities in Beijing and Hong Kong have repeatedly said the legislation is aimed at a few troublemakers and will not affect rights and freedoms, nor investor interests.