Rome - A consortium of private Italian investors on Friday made a binding offer to purchase the state's controlling stake in struggling airline Alitalia, according to a consortium statement cited in news reports.

The offer was presented to Alitalia's bankruptcy administrator, Augusto Fantozzi a few hours before a deadline at midnight local time (2300 GMT).

The bid came after talks between the Compagnia Aerea Italiana (Italian Air Company), or CAI, consortium, and unions representing Alitalia employees.

At one stage, CAI was reportedly on the brink of withdrawing its bid in the face of opposition from unions representing pilots and flight attendants. Earlier, CAI announced it had reached agreement with the main unions representing ground staff.

Prime Minister Silvio Berlusconi a strong proponent of CAI's bid, reportedly made a phone call to CAI president, Roberto Colaninno, in a last ditch effort to ensure the bid would be presented.

In late September, following often tortuous negotiations, CAI won an "in principle" backing from unions for a restructuring plan after making concessions on pay and contractual issues.

Since then, some of the unions have accused CAI of changing the terms.

ANSA news agency quoted CAI's Friday evening statement as saying the consortium made its offer conditional on European Commission, the EU's executive branch, approval of an Italian state loan to Alitalia announced earlier this year.

CAI's proposed offer is worth some 1 billion euros (1.25 billion dollars), and involves it employing some 12,500 Alitalia workers while laying off another 3,000.

The consortium has indicated that if its offer is accepted, it will seek alliances with other international carriers. Air France- KLM, Lufthansa and British Airways have indicated interest in taking part in the new venture. (dpa)