The worst-case scenario at the West Kowloon Cultural District project if the proposed HK$21.6 billion construction budget fell short was the delay of three phase-two performance venues, the government said yesterday. The construction budget could also accommodate costs increasing by an annual average of 3.4 per cent. Permanent Secretary for Home Affairs Carrie Yau Tsang Ka-lai said if unexpected circumstances increased costs, there would only be a delay to the project's phase two - which covers a grand 1,900-seat theatre, two medium-sized theatres and the extension of the mega museum M+. 'To the best of our knowledge and calculation, our estimated increase in the construction cost is realistic,' she said. Mrs Yau's deputy, Esther Leung Yuet-yin, said records showed construction cost increases would not exceed an average of 3.4 per cent a year over seven to eight years. The estimate included a risk premium and could accommodate increases of that size, although the government estimated the likely increase to be 2 per cent. Mrs Yau said the government would not reduce the size of M+, although advisers believe its mode of operation will be a long-term financial burden on the project. She said any reduction would distort the original expectations of the arts and cultural sectors and might need another round of consultation to get consensus. The government is seeking HK$21.6 billion from the Legislative Council, mainly for construction and hiring staff for the West Kowloon Cultural District Authority. The government will explain its funding proposal to a Legco subcommittee today.