The most immediate benefit for China of the "phase one" trade deal - once it is signed - will likely be an increase in its purchase of United States farm products, such as pork, poultry and soya beans, say experts.

But larger shifts in the bilateral trade balance will be demand-driven and depend on the market competitiveness of US products, they stress, after top officials signalled over the weekend that Beijing would resist being held to fixed purchase commitments.