The Australian and New Zealand dollars were holding hefty gains for the week on Thursday as markets wagered a peak for the COVID-19 pandemic could be on the horizon, even as the death toll mounted across the globe.

The chance, no matter how slim, that economic lockdowns might start to be loosened soon was enough to lift equities and commodity prices, and boost growth-leveraged currencies.

That left the Aussie up at $0.6223, having climbed 3.8% for the week so far and well away from last month's 17-year trough at $0.5510. It also cleared major resistance at $0.6215, which could allow a run to the next target at $0.6326.

The kiwi has added almost 2.4% for the week to reach $0.6002 , but still faces a tough chart barrier at $0.6067. Markets will be closed on Friday and Monday for holidays.

The Aussie quickly shrugged off S&P Global's decision to downgrade Australia's outlook to negative given it would be a year at least before the triple-A rating might be cut.

Three-year yields were a shade higher for the week at 0.28%, but aggressive buying by the Reserve Bank of Australia (RBA) kept them in line with its target of 0.25%.

Yields on 10-year paper rose a sharper 20 basis points for the week to 0.97%, partly in line with a move in US Treasuries and partly because the RBA had signalled it might slow bond purchases once markets had stabilised. New Zealand is also planning to borrow a lot more, with bond issuance for 2019/20 almost doubling to NZ$25 billion and over half of that to be sold by the end of June.