New Environment Minister Sussan Ley says farmers in the Murray Darling Basin should be allowed to "borrow" water reserved for maintaining the river's health, and federal approval for major developments must be streamlined to "give proponents more assurances" and reduce delays.

In an interview with The Sydney Morning Herald and The Age, Ms Ley also identified predatory starfish as the "most imminent" threat to the Great Barrier Reef as she flagged potential changes to the way Australia's natural assets are managed.

New Environment Minister Sussan Ley has flagged a suite of changes to natural asset protection. Credit:Alex Ellinghausen

The Liberal MP was returned with a 7 per cent swing against her in the rural NSW seat of Farrer, where concern about water allocations to farmers featured heavily in the federal election campaign.

Ms Ley's new portfolio captures the Commonwealth Environmental Water Office, which manages the majority of water for the environment recovered under the Murray Darling Basin Plan.