Doctors and other health professionals will be asked to identify people who are "vulnerable to being drawn into terrorism" as part of the government's redrawn counter-terrorism programme to be detailed on Tuesday.
The home secretary, Theresa May, will also try to deflect criticism that the £60m-a-year Prevent programme has been used to spy on the Muslim community by extending its coverage to the far right and animal rights extremists, as well as Islamist groups.
May has indicated that 20 of the organisations funded by the government over the past three years are to have their cash withdrawn after the decision to stop working with non-violent extremists.
David Cameron has pushed through the change despite opposition from Nick Clegg and Charles Farr, the head of the office of security and counter-terrorism, arguing that such engagement is like "turning to a rightwing fascist party to fight a violent white supremacist movement".