According to the new laws, farmers will have to reduce the number of birds that can be kept in existing houses, improve ventilation and lighting and stop "debeaking" -- removing a bird's beak which farmers say is done for safety reasons.

Latest figures show that 5.2 billion chickens are raised each year in the EU with an annual turnover of approximately 20 billion euros ($24.49 billion).

According to the new code of conduct, farmers will only be allowed to house 30 kg of chickens per square metre. There are now no limits on that and animal welfare groups sought a more ambitious figure of 25 kg.

"It's like looking in to your stocking at Christmas and you are happy with the outcome, but still missing something," Dil Peeling, senior policy officer with Eurogroup for Animal Welfare told Reuters.

"We are still studying the vote, but we are very happy with the debeaking ban and the greater competence issue."

The MEP's went a step further than the proposal of the European Commission - the EU's executive arm -- and voted to ban imports of chickens from outside the bloc which do not adhere to the same standards as set by the EU.

The decision could hit chicken meat exports of the two biggest EU suppliers -- Brazil and the United States -- which sold most of the 1.65 billion euros ($2.02 billion) worth of chicken meat imports to the EU in 2004.

Separately, the Commission adopted on Monday a five year plan to improve general animal welfare standards in the EU.

It proposed a range of measures aimed at improving standards for animals, promoting research into animal testing and support for international initiatives on animal protection.

The proposals follow an online survey of 40,000 people in which 80 per cent supported better labelling about how animals are raised and 67 per cent said this would influence their purchasing decisions.