Tough new powers to seize passports at the border from those suspected of travelling to Syria or Iraq for extremist activity will come into force in the UK from tomorrow.
The Counter-Terrorism and Security Bill received Royal Assent from the Queen which makes it an Act.
"This important legislation will disrupt the ability of people to travel abroad to fight and then return, enhance our ability to monitor and control the actions of those who pose a threat, and combat the underlying ideology that feeds, supports and sanctions terrorism," said UK home secretary Theresa May.
"The shocking attacks in Paris last month, in which 17 people lost their lives, and the many plots that the police and security and intelligence agencies continually work to disrupt, are clear evidence of the threat we face from terrorism.
"We have a fundamental duty as a government to ensure that the people who work to keep us safe have the powers they need to do so," she said.
Now, the UK home secretary will have the power to relocate those subject to Terrorism Prevention and Investigation Measures and require them to attend meetings with probation staff and others as part of their ongoing case management.
Other provisions - including a duty on specified bodies, including the police, prisons, local authorities, schools and universities, to have due regard to preventing people being drawn into terrorism; and measures which will enhance UK border security for aviation, maritime and rail travel - are set to commence in the coming months, subject to parliamentary approval of crucial secondary legislation before the end of March.
The new act will introduce new temporary exclusion orders, which will disrupt the return to the UK of a British citizen suspected of involvement in terrorist activity abroad.
It will improve the ability of law enforcement agencies to identify which device is responsible for sending a communication on the internet or accessing an internet communications service.
A voluntary programme introduced for people at risk of radicalisation - a legal requirement for public bodies so that it is delivered consistently across the country.
Use of the powers in the Act - which has undergone extensive parliamentary and public scrutiny, and has received cross-party support - will be subject to stringent safeguards, including suitable legal thresholds and judicial oversight of certain measures such as temporary exclusion orders.
During the passage of the bill, British Prime Minister David Cameron also announced an additional 130 million pounds which will be made available over the next two years to strengthen counter-terrorism capabilities.
This will include new funding to enhance the security forces' ability to monitor and disrupt terrorists and additional resources for programmes to prevent radicalisation.
