Video report by ITV correspondent Elaine Willcox.
Public venues must ensure stronger protection against terrorism under a new law introduced following the campaign of the mother of a Manchester Arena bombing victim.
Martyn Hett, 29, was one of 22 people killed during the attack at the end of an Ariana Grande concert on 22 May 2017.
After Martyn's death his mother, Figen Murray, has tirelessly campaigned to ensure public venues and local authorities have preventative action plans against terror attacks.
Now, after four years, the legislation known as Martyn’s Law is set to be introduced with the Government planning to publish draft legislation in early spring.
Prime Minister Rishi Sunak said he is committed to working with Ms Murray to improve security measures at public venues.
When asked by ITV News if the law would have stopped the Arena attack, if had been in place before the bombing, Ms Murray said: "I would like to think so."
"Had everybody there had this basic training," she added, "they would have been far more aware of suspicious behaviour.
"And the general public would have been [more aware] because there would have been an awful lot more people who had that training and knowledge under their belt."
Currently private and public owners of venues currently have no obligation to act on advice from specialist counter-terrorism officers about threats of a terror attack and how to reduce the risk.
Martyn's Law will cover all of the United Kingdom and follow a tiered model linked to the type of activity taking place and the size of the expected audience, the government said.
The law will also seek to improve how prepared a venue is without putting an undue burden on business.
The government will also establish an inspection and enforcement regime, issuing sanctions for breaches, and will provide statutory guidance and bespoke support.
What are the tiers?
A standard tier will apply to locations with a maximum capacity of more than 100 people.
Venues will need to undertake low-cost effective measures such as training, information sharing, and completion of a preparedness plan.
An enhanced tier will focus on high-capacity locations - those that can hold 800 or more.
Venues will be required to undertake an additional risk assessment that will inform the development and implementation of a thorough security plan.
The Prime Minister told Ms Murray the news on what would have been Martyn's 35th birthday.
“I got a phone call off Rishi Sunak himself on Thursday morning, which was incredible because it was actually Martyn’s 35th birthday,” she said.
“The Prime Minister knew about the birthday, so he mentioned it at the beginning, which was rather nice of him.
“I said to him it was the best birthday present I could have hoped for for Martyn.”
She added that her son would be “tickled pink” if he were here to hear about the legislation.
“He would be tickled pink, I would say, he would be really touched,” she said.
“But I think, on a more serious note, he would be really pleased that something as important as this kind of legislation, in his name, is going to be saving lives in the future.”
Praising Ms Murray’s campaign, Mr Sunak said: “The way the city of Manchester came together as a community in the wake of the cowardly Manchester Arena attack, and the amazing work of campaigners like Figen Murray who have dedicated their lives to making us safer and promoting kindness and tolerance, is an inspiration to us all.
“I am committed to working with Figen to improve security measures at public venues and spaces and to delivering this vital legislation to honour Martyn’s memory and all of those affected by terrorism.”
One leading figure in the night-time economy thanked Ms Murray for making a "difference."
Home Secretary Suella Braverman told the House of Commons of how "grateful" she was to Ms Murray and her fellow campaigners.
Ms Braveman said: “Their tireless efforts have helped inform our approach and the heart-breaking stories from survivors and their families are a constant reminder as to why we must deliver on this commitment to work together to improve public security.”