UPDATE 3-Italy's Salvini says bid for ASPI would be 'of great interest'

(Recasts with comments by transport minister)

ROME, Oct 2 (Reuters) - Italian Transport Minister Matteo Salvini said an offer for motorway operator Autostrade per l'Italia (ASPI) would be "of great interest," after government sources dismissed as "groundless" a report that it could support such a bid.

Bloomberg reported on Monday, citing anonymous sources with knowledge of the matter, that Italian construction magnate Matterino Dogliani was considering bidding for a controlling stake in ASPI.

ASPI changed hands last year in a 9.3 billion euro deal when a consortium comprising state-lender CDP bought it back from Italy's Benetton family, ending a legal wrangle over ASPI's motorway concession that ensued after a deadly bridge collapse.

Dogliani's family company Fininc is looking at teaming up with an international investment firm for a friendly offer of about eight billion euros ($8.4 billion) that would value ASPI at around 20 billion euros including debt, the report said.

Government sources said it was "completely groundless" to say that the executive of Prime Minister Giorgia Meloni was aware of the plan and might support it.

Salvini confirmed that the government was not aware of any "formal offer".

"However, if a great Italian entrepreneur can put together funds to support a key investment plan for Italy, such as ASPI's, ... it is certainly of great interest," the minister said in a statement.

He added he hoped a formal offer could be tabled so it could be examined in detail.

The consortium led by CDP, which included international funds Macquarie and Blackstone, last year bought ASPI from the Benetton family's Atlantia holding company.

A source close to Macquarie said it was "not engaged in any discussions with Fininc," adding the story appeared to be without foundation. CDP and Blackstone declined to comment.

The Benettons sold the asset, which manages around 3,000 kilometres of motorways in Italy, after criticism from the government for the collapse of a bridge along its network in Genoa in 2018, in which 43 people died. ($1 = 0.9518 euro) (Reporting by Alvise Armellini, Giuseppe Fonte, Andres Gonzalez and Elvira Pollina, Writing by Valentina Za; editing by Keith Weir and Christina Fincher)