(Adds debt markets, capex and ratings comments)
SYDNEY, March 22 (Reuters) - Australia Pacific Airports Corp, the owner of Melbourne Airports, said Australia's second-largest airport is considering selling bonds to refinance maturing debt and fund expansion.
The amount would depend on the outcome of the company's 2017 budget and capital expenditure plan, which was expected to be finalised in late April, Australia Pacific Airports treasurer and deputy chief financial officer Simon Milne said.
"The funding plan will ultimately be determined by the timing of the capital spending," Milne told Reuters in an interview on Monday.
Milne said he would consider issuing bonds in the Australia domestic market, euro, sterling and the U.S. private placement market.
Australia Pacific Airports Corp is privately owned and responsible for runways and terminals. It has a total of A$3.1 billion ($2.35 billion) in loans and bonds on issue, including a A$250 million debt issue maturing in August.
Milne, however, said he did not have to return to the capital markets because of undrawn bank facilities.
"We have liquidities that cover 6 to 18 months so that we go to the market when we want to, not when we have to," he said.
While Australia Pacific Airports, which also owns Tasmania's Launceston airport, flagged plans to expand existing operations, the associated costs could mean the loss of its A-minus ratings.
"If there is an opportunity to bring forward capital projects and provide shareholders' returns, (we would examine) the benefits of transitioning to a lower level," Milne said.
Australia Pacific Airports Corp is rated two notches above larger rival Sydney Airport by Standard & Poor's. The ratings agency expects revenue growth of at least 12 percent this fiscal year, while viewing the borrower's liquidity as adequate.
S&P said it was monitoring the company's solid 2016 capital expenditure programme of about A$450 million to A$500 million as well as annual dividends of A$160 million to A$180 million.
The ratings outlook is stable. ($1 = 1.3208 Australian dollars)