The board of Italy's troubled airline Alitalia has voted to accept an offer by Etihad Airways to invest in the company, and said it would move quickly to conclude the tie-up, the company's chief executive said.

"Today the Etihad plan was approved, and the board delegated myself and the chairman to study and rapidly come up with a draft of the final contract," Gabriele Del Torchio said.

Abu Dhabi-based Etihad is prepared to invest up to 1.25 billion euros ($1.7 billion) over the next four years, Italy's transport minister said on Wednesday.

Italy's flagship carrier Alitalia, which received a 500- million-euro government-engineered rescue package last year, risks running out of cash by August unless it can find a cash-rich partner.

In a statement, the privately held airline said it approved its 2013 balance sheet, without giving details.

It said only that it wrote down 233 million euros in charges and devaluations for 2013 "in preparation for future strategies".

A source with knowledge of the company's 2013 balance sheet said losses, excluding the write-down, amounted to about 290 million euros.

Alitalia is still negotiating with banks about restructuring about 700 million euros in debt, Del Torchio also said.-Reuters