The European Commission says farmers there have had enough time to adapt to the new rules, which will see the use of sow stalls limited to four-weeks after mating by the end of 2012.

The rules are in line with a new welfare code proposed for pigs in the country, which limits the use of sow stalls to four weeks from 2013, but with a complete phase-out by 2017.

The National Animal Welfare Advisory Committee is currently deciding on a final version of the code to recommend to the Minister of Agriculture by September, reports Radio New Zealand News.

Pork Industry Board chief executive Sam McIvor says farmers in the EU have been echoing what farmers here have been saying, in that the change will be costly.

But while farmers here are committed to meeting the new rules, he's heard that quite a few European countries are not ready.

But Mr McIvor says the board's concerns really lie with New Zealand's main competitors, the United States and Canada, where there have been no moves to restrict pig farming practices.

He says it's unfair that New Zealand producers will face restrictions, but imported product with inferior welfare standards won't.

Some 30 per cent of pork consumed in New Zealand is imported.

Pig farmers in Australia are not expected to face any restrictions until 2017, when the use of sow stalls will be limited.