Feb 21 (Reuters) - Europe's Airbus is closing in on a deal to sell as many as 20 A330neo wide-body airliners to Vietnamese budget carrier VietJet, industry sources said on Wednesday.

If confirmed, the multi-billion-dollar order could be announced as early as Thursday at the Singapore Airshow, they said.

Airbus declined to comment and VietJet did not immediately respond to a request for comment. (Reporting by Tim Hepher, Lisa Barrington; Editing by Kirsten Donovan)