SYDNEY—Top executives from Singapore Exchange Ltd. are visiting Australia this week, just days before the company is expected to formally apply for approval of its 8.4 billion Australian dollar (US$8.49 billion) takeover of local market operator ASX Ltd.

The head of SGX's listings department is leading the delegation to the rich mining state of Western Australia, home to more than 40% of the stocks listed on the ASX, including bellwethers Wesfarmers and Woodside Petroleum Ltd.

A spokeswoman for SGX said the visit was in response to an invitation from Western Australia's state government and that the company's officials will be meeting with ASX-listed companies in the state. Chief executive Magnus Bocker will arrive in Perth on Thursday to speak at a conference. An ASX spokesman said Mr. Bocker will be promoting to mining companies the benefits of the proposed SGX-ASX tie up.

The application to the Foreign Investment Review Board, or FIRB, for government approval is a watershed in the Asian exchange's bid to buy ASX, a move that has provoked fierce political debate in Australia. SGX first announced its offer for all the shares of ASX in October, in a deal that would create the world's fifth-largest listed exchange company, with access to a combined market worth US$1.9 trillion, according to analyst estimates.

Once the application is lodged with FIRB, the board has 30 days to make a recommendation, or seek a 90-day extension. Treasurer Wayne Swan must then decide whether to approve or reject the offer, a decision that could provoke political uproar in a country where foreign ownership and investment in assets deemed to be strategic remains sensitive. Under Australian law, no single shareholder can own more than 15% of the ASX and any regulation to lift that threshold must be considered in parliament for a 15-day period.

"With the Singapore and Australian stock markets moving towards an even closer relationship than present, it is vital that Singaporean investors understand the strength of Western Australia investments," said Kim Hames, deputy premier for Western Australia, in a statement.

SGX has so far offered several concessions to promote the deal, including adjustments to the board structure to increase the number of Australian members. Revenue generated from listings, transactions and fees on the Australian exchange would remain onshore.

SGX offered 22 Australian dollars in cash and 3.473 SGX shares for each ASX share, valuing ASX at 48 Australian dollars a share based on the closing price before the offer was announced. Based on Tuesday's closing price for SGX, the offer is valued at about 46 Australian dollars a share. ASX shares closed at 37.42 Australian dollars on Tuesday in Sydney.

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