Home Secretary John Reid will chair the first weekly meeting of a new security and anti-terrorism group.
John Reid announced a shake-up at the Home Office last month
Key government departments and leading security and intelligence agencies will meet at an undisclosed location.
The weekly gatherings will support Tony Blair's Monthly Ministerial Committee on Security and Terrorism.
Last month Mr Reid announced a Home Office shake-up, including a new Office for Security and Counter Terrorism and a separate Ministry of Justice.
Following the security meeting on Thursday, the home secretary will meet police chiefs from England and Wales to discuss what the reforms will mean for their forces.
Under the changes, the Home Office will retain responsibility for security and counter terrorism plus policing, anti-social behaviour, drugs, crime reduction, immigration, asylum and proposed identity cards.
As well as the Office for Security and Counter Terrorism, whose head has yet to be appointed, there will be a unit focusing on research, information and communications.
The new Ministry of Justice will be responsible for prisons, probation, sentencing and criminal justice policy.
Mr Reid said: "The new Office for Security and Counter Terrorism within the Home Office will bring a new drive, more cohesion and greater strategic capacity to our fight against terrorism.
"It will enable us to better respond to the new and increasing challenges we face in the all-important task of protecting the country's security.
"It provides a strengthened framework for the UK police and security services to disrupt terrorist attacks and bring those planning and carrying out terrorist attacks to justice."