Poland's prime minister on Tuesday defended a highly controversial court ruling on abortion that has ignited angry protests across the country, calling for an end to "barbarism".

Poland has seen six consecutive days of demonstrations against the decision which, when published, rule out abortions in all cases except rape and when the life of the mother is at risk.

"Acts of aggression, barbarism and vandalism are absolutely unacceptable," Prime Minister Mateusz Morawiecki told reporters, warning that any violent protests could lead to an "escalation".

"Attacks on religious symbols and churches will not be permitted," he said, after a series of protests in Catholic churches over the ruling.

As the prime minister spoke, there was another protest -- this time in the Polish parliament.

Left-wing lawmakers held up placards and shouted pro-choice slogans at Jaroslaw Kaczynski, the powerful leader of the ruling Law and Justice (PiS) party that supports the ruling.

The session was suspended amid angry scenes.

Poland, a predominantly Catholic country, already had some of the most restrictive abortion laws in Europe and many women travel abroad to terminate their pregnancies.

There have been six days of protests since the ruling
There have been six days of protests since the ruling AFP / Wojtek RADWANSKI

But the constitutional court ruled last Thursday in favour of further restrictions, stating that an existing law allowing the abortion of damaged foetuses was "incompatible" with the constitution.

The verdict is in line with the position of the governing nationalist Law and Justice (PiS) party, whose MPs had asked the court to rule.

Opponents of the ruling party say it puts women's lives at risk by forcing them to carry unviable pregnancies but supporters insist it will only stop the abortion of foetuses diagnosed with Down Syndrome.

There are already fewer than 2,000 legal abortions per year in Poland and the vast majority are carried out due to damaged foetuses.

But women's groups estimate that up to 200,000 procedures are performed illegally or abroad.

The ruling cannot be appealed but only comes into force if it is published in the journal of laws.

It is unclear when this will happen.

More protest against the ruling are planned in the coming days.

Poland