But a proposal to redevelop the Cockle Bay Wharf at the eastern end of the bridge and a separate proposal to rebuild the Harbourside Shopping Centre at its western end have drawn strong objections from the City of Sydney.

Both proposals, which were recently placed on public exhibition by the Department of Planning, confirmed long-held plans by developers to demolish the existing buildings and completely rebuild at both sites, with plans for tower blocks on either side of the Pyrmont Bridge.

The City of Sydney has lodged written objections to both plans, questioning the "appropriateness" of the towers close to the foreshore.

The $400 million redevelopment of the Harbourside Shopping Centre, which developer Mirvac purchased for $252 million in 2013, initially centred on Mirvac's plans to build a commercial tower on top of a new multi-storey shopping mall.

But under Mirvac's latest proposal, the tower will be residential, loom as high as 166 metres, and be positioned further south of the Pyrmont Bridge. It will still sit on top of a new shopping centre, which will have as many as five levels, comprising 52,000 square metres of retail space.

But the changes have failed to impressed the City of Sydney's planners, who described the proposal as "generally lacking context and certainty" and said the city was "strongly opposed" to the residential tower.

"The close proximity to the Pyrmont Bridge obliterate the heritage significance of the Bridge," senior planner Russell Hand said in the city's written submission.

Mr Hand also criticised the "scale and siting of the tower" as unsuitable for its location, adding that it would have "drastic shadowing impacts on the public foreshore and harbour".

"Permanent ownership of public land through strata-titled apartments is not consistent with the intent and purpose of Darling Harbour."

Opened by Queen Elizabeth in 1988, the Harbourside Shopping Centre is one of the remaining buildings from the original redevelopment of Darling Harbour initiated by the Wran government during the 1980s.

Mirvac's proposal described the complex as "outdated and in decline" and said a "carefully considered and staged approach" would be taken to the redevelopment.

"Harbourside is at risk of being left behind and undermining the significant investment being made in Darling Harbour that will see it return to the world stage as a destination for events and entertainment," the proposal stated.

Directly across the harbour, the proposal for a new office and retail complex at Cockle Bay, which will feature new bars and restaurants alongside the potential for a 235 metre high tower, has also drawn the consternation of the city.

"The city questions the appropriateness of a very tall tower on the foreshore," senior planner Christopher Ashworth noted in the city's submission.

While the development proposal doesn't specify the height of the office tower, the co-owners of Darling Park complex – GPT Wholesale Office Fund, AMP Capital Wholesale Office Fund and Brookfield – have already unveiled plans for a 44-storey office tower on the waterfront as part of the $1 billion redevelopment.

But the city's view is the area is "more suitable to lower-scale office accommodation" and the proposed tower is "far in excess" of the maximum height of the surrounding buildings, which is predominantly 80 metres.

Under the plans, the new Cockle Bay Wharf complex will sprawl over the Western Distributor, connecting the CBD to Darling Harbour, and include over a hectare of green public space.

The two proposals, though still in the formative stages of development, follow the massive $3.4 billion redevelopment of the Darling Harbour precinct over the past few years, led by the $1.5 billion International Convention Centre complex, which was completed in December.

Also facing the wrecking ball is the IMAX Cinema, which will be replaced as part of a new 20-storey development called The Ribbon, which includes a 588-room, six-star W hotel, restaurants and shops.