French shippers can expect road haulage rates to rise between 8 percent and 12 percent over the next few months to compensate for a truckers' labor agreement taking effect Oct. 1, according to French road haulers.

Four French road transport organizations announced Tuesday that they were advising all trucking companies in France to pass on to shippers the increased labor costs resulting from a "social contract" pushed through by the French government last year.Rene Petit, president of the largest French organization of trucking companies, the National Federation for Road Transporters (FNTR), said at a news conference that the costs of the agreement have been carefully studied and the price increases are "justified."

According to French courier companies and freight forwarders, the transport of small packages will rise by about 5 percent due to the added labor costs.

''The increase is essential for the survival of our companies," Mr. Petit said. "Any hauler that does not raise transport rates is not obeying the new rules."

A spokesman for the French Shippers Council, while admitting a blanket rate increase was inevitable, the exact amount should depend on individual contracts between truckers and their customers.

French truckers say shippers should not complain about the rise since road transport rates have fallen by one-fifth over the past five years due to the cutthroat competition within the industry.

The French government steered negotiations between unions, transporters and shippers to regulate working conditions of truckers.

The talks were a response to public outrage over the large number of road accidents involving trucks in France and calls for tighter control over the number of hours truckers are on the road and tougher safety checks on vehicles.

Under the terms of the labor agreement, truck drivers will be allowed to work a maximum of 240 hours a month (compared with the typical 270 hours now) and will have to be paid a minimum salary. The number of working hours is set to fall in 1998 to 220.

French road transporters say they are in a strong enough competitive position compared with trucking companies in other European countries to withstand the price increases.

According to estimates provided by the industry, French truckers have captured 78 percent of the market for trade with Italy and Spain and 55 percent of cargo transported by road between France and Germany.