The Asian Development Bank (ADB) has approved a $120 million loan in additional funding for a six-year government-led programme to improve the quality of primary education and ensure its expansion.

The loan will be complemented by co-financing from the European Union, the Global Partnership for Education, the United Nations Children's Fund, and the World Bank, the Manila-based lender said in a statement Sunday.

Third Primary Education Development Programme was launched in 2011.

ADB's original financing was a $320 million loan, and it agreed in 2011 to make more funds available if implementation was successful.

This was confirmed by a joint midterm review by the government of Bangladesh and its development partners completed in September 2014, which called for a greater focus on results.

The additional funds are expected to raise key performance indicators relating to student achievement, access and efficiency in Bangladesh, which has one of the largest primary school systems in the world with over 19.5 million children enrolled in about 106,000 primary schools.

The midterm review notes that the project has increased enrolment and reduced dropout rates across the country, but this trend is lower among disadvantaged groups such as children from small ethnic communities, children living in slums, and children living with disabilities. Disparities between schools and between rich and poor children still persist.

"Although the programme has helped Bangladesh make considerable progress on meeting its education targets enshrined in millennium development goals (MDG) two and three, much work remains to be done," ADB's senior social sector specialist Rudi Van Dael said.

"This additional funding will help deepen ongoing reforms, scale up successful project interventions, and complete already scaled-up activities," said the ADB official.

The ministry of primary and mass education is the executing agency of the project, to be completed by the end of June 2017.

ADB, based in Manila, is dedicated to reducing poverty in Asia and the Pacific through inclusive economic growth, environmentally sustainable growth, and regional integration.