Rihanna has tweeted Prime Minister Malcolm Turnbull and Minister for Foreign Affairs Julie Bishop, calling for them to pledge $200 million to an education charity chaired by former prime minister Julia Gillard.

The Work singer, who has been a spokesperson for the global charity since September 2016, called on the Australian government to donate to the Global Partnership for Education, an multilateral organisation that aims to improve access to education in the world's most disadvantaged countries.

Global Citizen founder Hugh Evans, Rihanna and Julia Gillard at the Global Citizen Festival in 2016. Credit:Twitter/Julia Gillard

"Hi Julie Bishop & Malcolm Turnbull, will you step up [with] a $200m pledge to #FundEducation at the Global Partnership for Education conference in Senegal tomorrow?" Rihanna tweeted on Friday.

"Kick off your first year on the #HumanRightsCouncil by giving the universal human right to education."