City planners have today given their backing to the first three phases of construction work on the £500 million Paradise development in central Birmingham.

Three separate applications were debated and approved by councillors for two new office buildings - One and Two Chamberlain Square - and new public space in the square next to the Council House.

The work will involve the demolition of Central Library and Paradise Forum shopping precinct which is yet to start earnest and had an original completion date of October this year.

The team behind Paradise said today this demolition work would now start "within weeks".

Paradise is an office-led development due to be completed in the mid-2020s and will comprise a hotel and eight separate buildings geared towards serving Birmingham's growing reputation as a key destination for corporate occupiers.

Construction work on One and Two Chamberlain Square, which will together have more than 350,000 sq ft of grade A office space, is due to start next year with both buildings expected to be finished before the end of 2018.

Pictures: CGIs of One and Two Chamberlain Square

The public realm work includes a new pedestrian street through the centre of the development, linking the upgraded Chamberlain Square to Centenary Square, but which drew a negative response from Birmingham Post readers this week with some describing it as bland and sterile.

Argent, the group behind Brindleyplace, is development manager for Paradise on behalf of Hermes Investment Management.

Argent's senior projects director Rob Groves said: "Now we have the city's permission, we will move forward on delivering these two exceptional office buildings and public space enhancements and bring our plans to create this prestigious business address at the civic heart of Birmingham into reality."

One Chamberlain Square will sit on the site of Central Library. It was designed by London-based Eric Parry Architects and has 172,000 sq ft of office space across seven storeys including space for restaurant and retail uses on the ground floor.

Two Chamberlain Square will be directly opposite and contain 182,000 sq ft of office space, also across seven storeys and with space for restaurant and retail units on the ground floor.

It was designed by Birmingham practice Glenn Howells Architects while the public realm element was created by Grant Associates Landscape Architects.