Chilean salmon producers are delaying harvests as they struggle to ship salmon to export markets, hampered by a national truck drivers strike now into its fourth day.

The strike, which began at midnight on Thursday sparked a scramble for replacement salmon in the US market at the end of last week.

By blocking parts of the country's main highway network, truckers aim to pressure lawmakers into approving a series of laws to halt violent attacks on drivers in the southern part of the South American nation.