Milk processing plants in Aberdeen and East Kilbride could close after Müller announced a consultation into the future of its operations in Scotland.

The firm said it was looking into moves to improve efficiency and competitiveness, putting 229 roles across the two sites at risk.

Meanwhile, the company revealed it would be investing £15m in its dairy at Bellshill in North Lanarkshire turning it into "a centre of excellence for dairy".

A 45-day consultation will now take place to examine the potential winding down of milk processing at Aberdeen and East Kilbride in South Lanarkshire.

The German food giant said both dairies are operating well below full utilisation with more than 60% of the capacity at Aberdeen dairy unused.

If the Aberdeen dairy were to close, all 43 farmers supplying the site will be offered the opportunity to continue supplying the business, according to the company.

Andrew McInnes, managing director at Müller, said: "We aim to reinvigorate our fresh milk and ingredients business in Scotland and propose to invest to make Bellshill a centre of excellence for dairy, benefiting consumers, customers, employees and farmers.

"It is important to stress that the status quo is just not viable in the medium term. Our Scottish dairies are inefficient and costly, which is putting a brake on the innovation and investment needed to stimulate new demand for dairy products.

"Our Aberdeen dairy is operating at less than 40% of its capacity and milk production from farmers in the north east is far in excess of customer requirements in the area.

"Our small dairy in East Kilbride makes products including flavoured milks and potted cream and we believe that we can gain important efficiencies by relocating that production to Bellshill, which is nearby.

"We will enter the consultation with an open mind and will rigorously assess the situation and listen to our colleagues before arriving at a decision."

NFU Scotland's north east chairman Roddy Catto said: "The 43 dairy farmers supplying the Müller site at Aberdeen, which includes myself, have a lot to think about ahead of a meeting with the company on Friday morning.

"We need to hear more about the investment plans at Bellshill, what that might mean to the Müller business and balance that against any additional transport costs we would face as Müller suppliers were the Aberdeen site to be wound down.

"The meeting with Müller must leave all dairy farmers in the area with a clearer view on what these proposals will mean, so that farmers can take an informed decision now on their future in milk production."

Councillor David Aitchison, chair of the infrastructure services committee at Aberdeenshire Council said the announcement was a "further blow" to the dairy industry.

He said: "Aberdeenshire Council is deeply concerned at today's announcement by Müller Milk and Ingredients to begin a consultation to examine the potential winding down of processing at dairies in Aberdeen and East Kilbride, potentially affecting 229 posts.

"This has far-reaching implications on dairy farming in Aberdeenshire - an industry which is already struggling in a highly price-competitive market.

"The announcement to close the milk processing site at Tullos in Aberdeen will have significant implications on the workforce, as well as our dairy farming industry, who will be faced with transporting their milk to Belshill. This is a further blow to an industry which is struggling to make Scottish dairy more competitive with overseas imports, risking the national viability of the entire sector."