"I've spent a lot of time on the committee, and I think it's time wasted," he told members at the committee's quarterly meeting Thursday.

"There are other ways for me to address the issue [of harbor preservation] that would cost me less time and would be more effective than the many hours I've spent here."

Due to a lack of leadership, the two- year-old committee had failed to work as a "proper interface" between the public and the government, he said.

For instance, despite his repeated calls for a review on the Central waterfront area, government members were obstinate about postponing the task until July - after the proposal for a HK$5 billion government headquarters at Tamar is expected to pass through the Legislative Council.

"So I'm not willing to sit here and waste my time if that's the attitude from the other side," he said.

He added that he and other activists would soon be holding several public forums on the planning of the Central harborfront to talk about the "real issues."

Zimmerman's relinquishment of the business representative post on the 29-member committee comes fast on the heels of his resignation in February from the executive committee of the Harbour Business Forum - two events he admits are related.

It also comes at a tense time when politicians and businesses alike are feeling the pressure to back the Tamar proposal, according to sources.

"Now it's up to them to find their own voice, to step up, and to not stand down when the heat gets too hot in the kitchen," Zimmerman said.

He added, in closing: "I look forward to working together with all of you, because I will definitely not shut up outside this committee."

Deputy Secretary for Housing, Planning and Lands Robin Ip Man-fai responded by gesturing at the handful of officials present at the meeting, insisting the government's support was more than evident.

"The committee has done a great deal in the past few years ... I cannot agree that not enough resources have been put in," he said.

Earlier in the meeting, committee members debated whether legal advice should be sought to ensure reclamation for the proposed Central-Wan Chai bypass corridor would pass the "overriding public need" test, in accordance with a 2004 Court of Final Appeal ruling. Since the ruling, reclamation works in Hong Kong have come to a standstill.

Government officials expressed an eagerness to consult lawyers for clarification on the term "reclamation."

They wondered, for example, whether pilings used to support a flyover or a pier would constitute reclamation as they would technically lie on the seabed.

But property surveyor Nicholas Brooke advised against going into such detail, warning that such an approach would steer the committee off-track.

"I caution against proceeding in too formal a manner and bogging ourselves down in fine print," he said.

"We should focus on the outcomes, and then market these outcomes to groups and persuade them they're in the best interest of Hong Kong. We need to convince them to adopt a pragmatic approach."

Zimmerman agreed, saying the 2004 ruling may not have considered reclamation for public needs, such as piers or other recreational facilities.

"The government is stifled right now. They're so worried about that ruling that they're not coming up with a strategy," he said after the meeting.

"We need to discuss principles during the planning stage - if you build more developments, you'll eventually need more roads, which means more reclamation."

He said that, while the building of the Central-Wan Chai bypass could be excused because it was proposed before the court's ruling, it should not be used as justification to pursue further reclamation in the same manner.