MILAN, May 21 (Reuters) - Stellantis is removing the Italian flag from the rear bumpers of its Polish-produced Fiat 600 after Italian authorities repeatedly accused the carmaker of being misleading over the origin of vehicles produced abroad.

The group on Tuesday said the decision was taken independently with the aim of "operating with complete and absolute transparency regarding the place of assembly of its products and to prevent any misunderstandings in this regard".

"Stellantis is firmly convinced that it has always acted with complete propriety in this regard," it said in a statement.

The news was initially reported by Milano Finanza on its website. The green, white and red colours of the flag had been in horizontal stripes in three small indents on the bumper.

The decision is part of a broader clash between Rome and Fiat owner Stellantis over the automaker's declining production in the country. Giorgia Meloni's nationalist government has openly criticised Stellantis for manufacturing cars of historic Italian brands such as Fiat or Alfa Romeo in lower cost countries.

Stellantis earlier this year decided to change the name of its latest Alfa Romeo model, which is also produced in Poland, from "Milano" to "Junior" after Italy's Industry Minister Adolfo Urso said the name violated a law targeting "Italian sounding" products that falsely claim to be Italian.

Last week fiscal police seized more than 130 Fiat Topolino minicars imported from Morocco that were carrying a sticker with the colours of the Italian flag on their doors.

Stellantis on Tuesday said the colours of the Italian flag on the Fiat 600, as well as on the Topolino, were only meant "to indicate the entrepreneurial origin of the product", designed and styled in Italy.

Stellantis said it had always clearly stated that the Fiat 600, officially launched last year, was being assembled in Poland. (Reporting by Giulio Piovaccari; Editing by Alison Williams)