Activists from the radical feminist group Femen have staged a topless protest in the Spanish Parliament against plans by the conservative government to reform abortion laws.

Standing in the public gallery of the lower house in Madrid, three 'sextremists' - as Femen calls its members - took off their tops and chanted "abortion is sacred" while Justice Minister Alberto Ruiz-Gallardon was speaking.

One of the activists climbed up onto a gallery railing and wrapped her arms around a pillar.

The three women, who had the words "abortion is sacred" also emblazoned across their naked chests, were dragged away by parliament ushers after a few minutes.

"Today in Madrid topless Femen sextremists have disrupted the working session of the Catholic Spanish Parliament for its intention to ban abortion," Femen announced afterwards, and claimed the raid was the first in a series of stunts it intends to perform in Spain as part of a campaign against the reform advocated by Ruiz-Gallardon.

Ruiz-Gallardon opposes Spain's current liberal regulations, approved by the socialist government led by José Zapatero in 2010, which give women the right to freely abort up to the 14th week of pregnancy.

The new government led by Prime Minister Mariano Rajoy plans to make abortion illegal unless except under certain conditions such as rape and health risks for the mother.

Femen has carried out a number of high-profile protests across Europe including topless marches in Paris and an ambush of Italy's former Prime Minister Silvio Berlusconi.