* Says still aiming to sell chip unit
* Can walk away from deal if no approval by May 28 - sources
* Expects to gain 970 bln yen profit from sale
* Plans to use proceeds for investment, share buybacks (Recasts with CEO comments on Chinese antitrust review)
TOKYO, May 15 (Reuters) - Toshiba Corp is upbeat about the prospects of clearing China's antimonopoly review of the $18 billion sale of its chip unit, its CEO said, dismissing reports it may pursue alternative plans if the review drags beyond the deal's deadline.
"We haven't heard anything negative from Chinese regulators," Chief Executive Nobuaki Kurumatani said at an earnings briefing on Tuesday.
"We haven't changed our stance (on the sale)," he added. "We aren't in any discussions (for alternative plans) based on the premise that the deal is cancelled."
The Japanese conglomerate last year agreed to sell its prized flash memory chip unit to a consortium led by U.S. private equity firm Bain Capital LP and South Korea's SK Hynix Inc at a time when the conglomerate was desperate for cash.
People familiar with the matter told Reuters that if the deal is not approved by Chinese regulators this month, Toshiba - which is no longer in need of immediate funds - may seek to drop the sale in favour of other options including listing the unit directly.
The people said the China's review is due for completion by May 28. They also cited concerns of China delaying reviews of major global chip deals due to Sino-U.S. trade friction.
Asked how long Toshiba can wait, Kurumatani said, "We don't think the Chinese regulators will remain silent. They will make some response."
If approval is not granted, Toshiba can walk away from the deal. It is no longer desperate for cash after a $5.4 billion new share issue to foreign investors late last year. Some activist shareholders have opposed the sale, arguing the deal significantly undervalues the unit.
Kurumatani on Tuesday repeatedly said there was no change to the plan to sell the unit. The company will use the sale proceeds to invest in growth areas and make returns to shareholders including through share buybacks.
The company expects to post 970 billion yen in profit from the sale, boosting net income by 33 percent to 1.07 trillion yen ($9.75 billion) this financial year.
That would mark a second consecutive year of profit after years of financial crisis due to accounting scandals and cost-overruns at its U.S. nuclear unit Westinghouse.
The flash memory chip business accounted for nearly 90 percent of Toshiba's operating profit in the year ended March, as Toshiba struggled to grow other key businesses such as energy and social infrastructure.
($1 = 109.7400 yen)
Reporting by Makiko Yamazaki; Editing by Edwina Gibbs and Christopher Cushing