VIJAYAWADA: Andhra Pradesh government agency today initiated an international competitive bidding process through the 'Swiss Challenge' approach for development of "start-up area" of the state's new capital city Amaravati.The area is spread over 6.84 sq km (1,691 acres).Andhra Pradesh Capital Region Development Authority (APCRDA) has invited competing counter proposals from eligible prospective bidders for selection of the Master Developer for the capital city.The AP government entered into a memorandum of understanding with the government of Singapore in December 2014 for development of the new capital city on the banks of Krishna river, between Vijayawada and Guntur.The Singapore, in turn, nominated Ascendas- Singbridge and Sembcorp Development Ltd to participate in the development of Amaravati as the Master Developer.The Singapore consortium on March 12 submitted a suo motu proposal, through 'Swiss Challenge' approach as per the AP Infrastructure Development Enabling Act-2001, to be the Master Developer of Amaravati.The consortium estimated the cost of developing infrastructure in the "start-up area", which includes a central business district, commercial hubs, business parks and high-density residential zones, at Rs 3,137.3 crore.It proposed to undertake development of the area in three phases over a period of 15 years (five years for each phase).The State Cabinet , on June 24, approved the Singapore consortium's proposal and it was subsequently notified by a Government Order (GO) on July 4.Based on the GO, the APCRDA today invited international competitive bids from eligible developers to counter the Singapore proposal.Under 'Swiss Challenge' route, a developer is asked to presents a bid. Then, other prospective developers would be asked to present counter bids. If the latter is lower, the first bidder will be asked to submit another bid. If the first bidder comes up with lower bid, then he gets the right or if he fails, the one with lower bid gets the project.September 1 has been set as the last date for submitting the competing counter proposals.