KUALA LUMPUR, Sept 7, 2007 (AFP) - Malaysia's government has urged a peaceful resolution to a row over a planned cull of thousands of pigs which triggered a standoff between riot police and ethnic Chinese farmers.

Deputy Prime Minister Najib Tun Razak insisted the furore was not a racial issue, and that authorities in Malacca state which ordered the mass slaughter were merely trying to curb environmental pollution.

"They (the breeders) had been warned not to pollute the area," he said late Thursday according to the official Bernama news agency.

Najib said the standoff, which forced the culling operation to be called off as farmers and their families faced off against thousands of official personnel to protect their pigs, should be solved through negotiation.

The Malacca state government said Tuesday that some 50,000 pigs on unlicensed farms would be culled, arguing that the stench and pollution from the illegal sites had become unbearable.

State secretary Ismail Salleh said that the number of pigs in the state should not exceed 50,000, but that there were about 120,000 in Malacca.

More than 60 percent of Malaysians are Muslim and consider pigs and pork unclean. The country's pig farmers are mostly from Malaysia's sizeable Chinese population.

Malacca state government spokesman Nur Azmi Ahmad said the cull had been stopped indefinitely, after only 2,000 pigs were slaughtered on Tuesday.

"But there were so many protests and in some places some of the farmers were very angry and stopped anyone from going into the farms," he told AFP.

"At this stage, we have agreed to stop the culling so that the farmers can find more suitable land, especially those operating without licences."

Opposition leader Lim Kit Siang called for the culling order to be revoked immediately, condemning the operations as "arbitrary, unreasonable and inconsiderate".

He said the mobilisation of some 2,000 personnal including from the riot unit and immigration enforcement had been a "major blot" on celebrations for Malaysia's 50th anniversary of independence last month.

"The high-handed method ... showed utter contempt not only for the citizenship and fundamental rights of the pig farmers but also the principle of the rule of law in the country," he said in a statement.