The Transpacific Stabilisation Agreement (TSA) said its members, including Maersk Line and Mediterranean Shipping, planned to incrementally raise US-Asia route rates from next month, with further increases in November and December. It did not give more details.
An increase in demand is usually seen in the run-up to the US Thanksgiving holiday and Christmas season in the West.
TSA said carriers saw a bottom in the market and expected a recovery in the fourth quarter. "US-Asia freight rates have fallen to historically low levels," TSA-Westbound executive administrator Brian Conrad said.
Conrad also said current rates did not fully cover costs in many cases, and the increases were needed to halt damaging rate erosion.
Shipping lines usually introduce general rate increases during the second and third quarters, but their effect is often minimised by competitive factors.
In the first week of this month, the China containerised freight index dropped 1.5 per cent from the previous week to 820.91 points, 24 per cent below the index average for last year.
The China-Europe component fell 5 per cent in the same period. Rates to the US west coast rose 1 per cent but fell 0.4 per cent to the US east coast.
"All lines will launch [general rate increases] at every opportunity, but very few have managed to stick so far in 2015," said Andy Lane, a partner at Container Transport International Consultancy. "Rates are most volatile on Asia-Europe routes. However, no trade is immune from the global oversupply."
Daniel Meng, an investment analyst at CLSA, said US-Asia trade growth was better than expected and that the price increases might be possible.
However, he said "there is still big concern about the slowdown of the US recovery".
"Overall, the downtrend in freight rates will extend in the short term, given new ship supply will reach a peak in the fourth quarter," Meng said.
"The reason shipping companies still try to raise rates is because the prospective higher price may help them give less discount."
According to estimates from the Clarkson Group, global container shipping will see capacity growth of 6.5 per cent this year, while demand growth will only be 5.1 per cent.