MILAN, June 17 (Reuters) - A Stellantis-led joint venture has started production of electric vehicles of China's Leapmotor at Stellantis' Tychy plant in Poland, analysts at Jefferies said, quoting Leapmotor's management.

Jefferies said in a report late on Sunday that Leapmotor's management said at an analyst call the first units of its T03 small EV rolled off Stellantis' assembly plant in Poland last week and was on schedule for mass production in September.

Reuters had reported in March, citing two people close to the matter, that Stellantis had chosen its Polish facility as the first production base in Europe for Leapmotor's cars, primarily for cost-saving reasons.

Stellantis did not immediately respond to a Reuters request for comment.

Stellantis and Leapmotor have created a joint venture, led by the Franco-Italian automaker with a 51% stake, giving Stellantis exclusive rights to build, export and sell Leapmotor products outside China, a first for a legacy Western automaker.

The venture, called Leapmotor International, is part of a wider cooperation between the two groups, which sees Stellantis buying a 21% stake in Leapmotor in a $1.6 billion deal.

Jefferies said the JV plans to manufacture a second model at Stellantis' Polish plant, the Leapmotor's A12 SUV, starting from the first quarter of 2025. Leapmotor has also started to prepare localized production of components, it added.

Manufacturing costs at the Polish plant amount to around 400-500 euros ($428.08-$535.10) per car, similar to those at Leapmotor's base in China, versus around 1,000 euros in Italy, the management said according to Jefferies.

Leapmotor plans to manufacture its C10 SUV in China and export it to Europe at an initial stage as this model could be sold at higher prices, Jefferies said.

The European Commission last week announced extra duties on imported Chinese EVs from July. They will amount to an additional 21% for Leapmpotor.

($1 = 0.9344 euros)

(Reporting by Giulio Piovaccari, editing by Gavin Jones and Rashmi Aich)