PARIS — President Nicolas Sarkozy of France told his cabinet on Wednesday that he would put forward a bill in May to ban the wearing of the full veil in public places in France, despite a warning from senior legal authorities that the bill may be unconstitutional.

Mr. Sarkozy wants a bill that goes farther than initial proposals, including a ban on wearing the full veil — the niqab, which leaves only the eyes uncovered, and the burqa, which is almost unknown in France — from streets, markets and shops, according to his spokesman, Luc Chatel.

The full veil “hurts the dignity of women and is unacceptable in French society,” Mr. Chatel quoted Mr. Sarkozy as telling the cabinet. The idea of a ban is popular with the French and with his own political party, while Mr. Sarkozy’s own standing in the opinion polls has rarely been lower.

An earlier proposal from a panel of the National Assembly suggested a bill banning the full veil in public places belonging to the state, like schools and public buildings, and in areas where facial recognition is vital for security reasons: airports, banks and even public transport.