Police say snipers and special agents will be stationed around Brisbane during next year’s G20 summit.

In November next year world leaders will descend on Brisbane, along with a huge entourage to attend the summit at the Brisbane Convention and Exhibition Centre.

Security measures are likely to include the closure of major roads between the airport and CBD in the week of the summit.

More than 5,000 police officers from across the country and New Zealand will be put on duty and Queensland Police will be given a second helicopter.

Deputy Police Commissioner Ross Barnett says it will be the biggest peacetime security operation the state has ever seen.

"In the 150 years we've been a department, we haven't had a challenge anywhere near as big as G20," he said.

Assistant Commissioner Katarina Carroll says community consultation will begin in two months.

"We have got a comprehensive engagement team; not only dealing with residents, business, the community across the gamut," she said.

The Defence Force has been enlisted to control major hubs across the city which are likely to include the airport and an exclusion zone around the conference venue.

The Queensland Government is receiving nearly $100 million of the $370 million federal G20 budget for preparations.

During the summit there will be restricted access to buildings in the area, and workers in Brisbane will be given a public holiday on November 14.