of A$3.5 billion (1986 terms) was established, and the submitted proposals were narrowed down in October to Blohm + Voss's MEKO design, the M class offered by Royal Schelde, and a scaled-down version of the British Type 23 proposed by Yarrow Shipbuilders. The Type 23 proposal was eliminated in November 1987, with the other two going into a development phase where the designer partnered with an Australian shipbuilder: Blohm + Voss with AMECON, and Royal Schelde with Australian Warship Systems. On 14 August 1989, the Australian government announced that AMECON had been awarded the tender for construction of the Anzac class based on Blohm + Voss' modified MEKO 200 design. Although both the MEKO 200 and M-class designs met the design requirements, the MEKO design was selected as more ships could be purchased for the budget cost. The A$5 billion contract was, at the time, the largest defence contract awarded in Australia. The decision was made despite ongoing debate in New Zealand over the project. New Zealand committed in principle to the purchase of two frigates plus the option for two more on 7 September, and the contract for the first two ships was signed on 10 November. In 1992, the Australian Force Structure Review contained plans to replace the three Perth-class guided-missile destroyers and four of the six Adelaide-class guided-missile frigates with air defence vessels. The initial proposal – to build an additional six Anzac-class frigates configured for wide-area anti-aircraft warfare – did not go ahead as the Anzac design was too small to effectively host all the required equipment and weapons. Instead, the RAN began to upgrade the Adelaides in 1999 to fill the anti-aircraft capability that would be lost when the Perths left service between 1999 and 2001, and began work on a long-term replacement of the destroyers with what became the Hobart-class air warfare destroyer. New Zealand controversy From the late 1960s decision of the UK government to withdraw the Royal Navy from East of Suez in the early 1970s considerable doubt existed within the RNZN, government, and community about the continuing relevance, viability, and usefulness of an RNZN force of 3 to 4 frigates. The option of the United States Coast Guard's (USCG) Hamilton-class cutters was seriously considered as an alternative to the order of HMNZS Canterbury in 1968, which was approved under the understanding that New Zealand would hold continued access to the UK