Fortescue Metals Group’s latest bond sale appears to be a sign that debt markets are bouncing back.

The iron ore miner on Wednesday announced it was seeking to raise $US1 billion ($A951.20 million) from a bond offering to fund its expansion plans in Western Australia’s Pilbara region.

Proceeds will be put towards a near tripling of annual iron ore production to 155 million tonnes by the end of June 2013, and the purchase of a mining fleet.

Fortescue last year and in 2010 upsized offers of senior unsecured notes to $US1.5 billion, from $US1 billion, after strong demand.

The company has previously said that it expects its $US8.4 billion ($A7.99 billion) production expansion will be funded through a mix of bank or bond debt, cash on hand and cash flow from operations, with the mix depending on market factors including iron ore price.

Shares in Fortescue finished up six cents, or 1.04 per cent, at $5.83.