President Jacques Chirac's party expressed its "most acute concern" Friday about a bill that could lead to legal recognition for unmarried couples.

The conservative Rally for the Republic party described the bill in a statement as "a decisive step toward the creation of a substitute for marriage and a parody of the family."The bill - known as the Civil Solidarity Pact - is due to go before parliament Oct. 9.

Bill supporters, including several pressure groups, met Friday with Prime Minister Lionel Jos-pin's advisers to discuss the text.

"The government seems to agree to most of our demands that we've been pushing for seven years," said Jean-Paul Pouliquen, a spokesman for a loosely aligned association that favors the bill.

Although the exact nature of the bill is not yet known, it is expected to include tax and inheritance benefits. Some government officials have charged it could cost the state up to $1 billion per year in lost revenue.

The prospect of the bill prompted some 12,000 mayors - mainly from the French right - to sign a petition in May, saying they feared it would lead to the legalization of homosexual marriage.

French gay groups that backed the left's election victory in June 1997 have complained that the government has been dragging its feet on the legislation.