The UK cannot be “passive in the face of malign covert activity” from hostile states, Home Secretary Priti Patel is expected to say, as she calls on MPs to back “vitally important measures” to overhaul espionage laws and bolster security powers.

First introduced in the Queen’s Speech last month, the National Security Bill is due to face its first legislative hurdle in the House of Commons on Monday when it goes before the lower chamber for its second reading.

The Home Office says the Bill will “completely update our espionage laws, provide UK law enforcement and intelligence agencies with new measures to disrupt modern threats, and bring in longer prison sentences for people who seek to harm our country”.

But the Bill is not without controversy, and Conservative former Cabinet minister David Davis is among those who have expressed reservations.

The Guardian reported that Mr Davis said: “This bill is drafted so loosely that it could let ministers off the hook if they authorised crimes like murder and torture from the safety of their desks in Whitehall.

“I urge colleagues to constrain it to actions appropriate to our aims and civilised standards.”

Ms Patel is expected to tell MPs the country must stay ahead of varied and persistent hostile threats, and that the Bill has been designed in consultation with the security services and will provide a range of new offences alongside updated investigative powers and capabilities.

Priti Patel (Andrew Matthews/PA)
Priti Patel (Andrew Matthews/PA)

The Home Secretary is also expected to cite Russian aggression against Ukraine to make the case for strengthening defences against state threats.

Ms Patel is expected to say: “The terrible chemical weapons attack in Salisbury by the Russian state is just the most obvious of the types of threats we now face, but state threats come in multiple forms.

“We cannot be passive in the face of malign covert activity designed to interfere with our national security, economy, and democracy.

“We all have a responsibility to our constituents and to our country to keep them safe.

“I urge the whole House to support the vitally important measures in the National Security Bill.”

The Government has previously described the Bill as “the biggest overhaul of state threats legislation for a generation”, saying it will enhance the UK’s ability to “deter, detect and disrupt state actors who target the UK, preventing spies from harming our strategic interests and preserving the integrity of our society”.

It will also restrict “the ability of convicted terrorists to receive civil legal aid” to ensure that “terrorists cannot gain civil damages which might fund terrorism”.

The boss of the MI5 security service, Ken McCallum, last month welcomed an overhaul of espionage laws, and described the UK as being in a “contest” with other states trying to undermine national security and interfere with democracy.

Asked about Mr Davis’ criticisms, a Home Office spokeswoman said: “The amendment to the Serious Crime Act will only remove the risk of individuals facing criminal liability where they are carrying out authorised lawful activities deemed necessary, in good faith and following proper procedure.

“Put simply, the Government believes it is not fair to expect the liability for this action to sit with an individual UK intelligence officer or member of the armed forces who is acting with wholly legitimate intentions.”