Farmers protesting the low price of milk have blockaded the distribution centres of retailers in Belgium, including Colruyt, Carrefour and Delhaize.

The protest started on Sunday (28 June) at a Colruyt distribution centre and then spread to other retailers' distribution centres.

A spokesperson for Colruyt confirmed that the blockade has already had an impact on stock levels.

"We are seeing problems with stock levels for fresh produce, dairy and meat in particular. This represents a large disruption to normal operations," the spokesperson said.

Condemning the "illegal" protest, Colruyt said in a statement that it could cost the retailer "millions of euros".

According to Colruyt, farmers have also disrupted normal operations at supermarkets by parking tractors in car parks and "demanding milk" to distribute to consumers.

Delhaize confirmed that farmers had also blocked one of its distribution centres, while tractors were used to block the entrance to a Belgian distribution centre for France's Carrefour.

It is unclear how long the protest will last, with some farmers reportedly threatening to maintain the blockade into next week.

A spokesperson for the European Milk Board told just-food that the problem stemed from the fact that farmers are not being paid enough to cover their production costs.

Protests have been staged throughout Europe, as farmers look to raise awareness of problems in the sector.

European farmers have called on the EU to cut milk production quotas, in order to ease oversupply on the market and force prices up. However, the EU has resisted such pressure and reaffirmed its intention to gradually phase out milk production quotas all together.