The government has seen off a controversial plan to replace Section 28 with a tough new amendment requiring parental consent.

Peers defeated, by 180 votes to 130, an amendment which would have allowed parents to object to inappropriate sex education.

The vote effectively paves the way for the removal of the controversial clause from the statute book.

Critics said the amendment effectively restored Section 28.

The Lords vote followed a Commons decision to scrap the law which prohibits the promotion of homosexuality in schools.

Conservative Baroness Blatch led peers in calling for Section 28 to be replaced with a new law giving parents new powers.

She attacked an "aggressive reluctance" to let parents made decisions on what is right for their children.

Ahead of the debate she wrote to other members of the upper house asking for their support for alternative to the controversial clause.

But she faced opposition from peers including Lord Alli and Lord Puttnam who wrote to peers calling on them to vote against the amendment and back the outright repeal of Section 28.

Whilst the government offered a free vote on the issue, local government minister Lord Rooker urged peers to oppose the amendment.

"Let's not beat about the bush. This is about keeping Section 28 on the statute book," he said.

In a vote earlier this year MPs voted for the clause to be scrapped outright.

But family values campaigners in the House of Lords had expressed strong reservations about such a move.

Baroness Blatch said her new amendment would cover both homosexual and heterosexual sex education.

She cited sex pamphlets designed for children which detailed over 19 different sexual positions and suggested children as young as 11 buy condoms as "homework".

The former education minister told the House that she wanted to prevent children being forced to read the "worst forms" of sex education - covering practices such as anal intercourse and the use of sex toys.

"To discuss sado-masochism, bondage and sex orgies is not appropriate," she said. "Why should parents not enjoy a legal right to be consulted and to see the materials used."

Her move followed a similar attempt by the late Baroness Young, who successfully won peers' backing to retain Section 28.

Several peers expressed reservations that children could be exposed to explicit material unless a replacement law was put in place.

"My concern, and that of Lady Young before me, has always been the protection of children from the worst form of sex education," Baroness Blatch said ahead of the debate.

Baroness Blatch insisted her new clause was not anti-gay. "The benefits of doing it this way are that it gets away from the sterile debate about homosexuality," she said.

Openly-gay Labour peer Lord Alli said the amendment was "unworkable" and would "reinstate Section 28".

"This debate has long since lost any sense of proportion, reason and logic," he said.

Lord Alli added that the repeal was supported by a wide range of children's charities, including the NSPCC.

Following a series of skirmishes in the Lords chamber he accused Baroness Blatch of attempting to secure support for a "wrecking amendment".

And he urged peers to back the total removal of Section 28.

"The measure is supported by a powerful coalition. It is a coalition which cares about children and their welfare," he said.