The federal government will double its funding for breast care nurses so that nearly 100 of them support women with breast cancer.

New funding of $27 million will add another 41 McGrath Breast Care Nurses by 2022/23 to the 57 currently funded by the government, Prime Minister Scott Morrison and Health Minister Greg Hunt announced on Saturday.

"More than 30 specialist nurses will now be dedicated to supporting metastatic breast cancer patients and their loved ones," they said in a statement.

"Metastatic breast cancer requires complex care and these nurses will now be able to spend more time supporting patients and their families."