Prime Minister Malcolm Turnbull is to unveil a multimillion-dollar plan to protect the Great Barrier Reef against mass bleaching.

The plan, to cost about $60 million over the next 18 months, will include funding farmers to reduce sediment run-off and innovative research, News Corp says.

A supplied image shows bleaching damages on the Great Barrier Reef. Credit:AAP

Mr Turnbull was expected to announce the plan in Townsville on Monday, supported by leading scientists.

Last week, the federal and Queensland governments issued an open call to the world's top scientific minds to help save the reef.