HO CHI MINH CITY (Reuters) - Vietnam's popular karaoke bars, renowned for hard drinking and prostitution, face tough new restrictions starting in July, according to a government decree.

The decree, issued this month by Prime Minister Phan Van Khai and shown to Reuters Wednesday, bans karaoke bar patrons from drinking spirits, imposes fines for public drunkeness and limits the number of servers to one person per room to discourage prostitution.

From July 1, drinking spirits in karaoke lounges is subject to a fine of up to 1.5 million dong ($94), equivalent to a monthly salary of a government official. Public drunkeness in any place out of the home including in clubs and restaurants, is punishable by up to 500,000 dong ($31), the decree said.

Lounge owners would also be fined up to 4 million dong ($250) if they use more than one person per room.

Karaoke is not only recreational but also widely popular business etiquette in the Southeast Asian country of 83 million.

Last week, state oil monopoly Petrovietnam's financial arm ordered 21 officials to write "self-criticism" reports for not singing karaoke at a business contract-signing ceremony.