The Islamic Development Bank (IDB) has relaunched its infrastructure fund with backing from Saudi Arabia, Bahrain and Brunei, aiming to raise $2 billion - almost triple the size of the original fund.

Jeddah-based IDB, a multilateral lender that promotes economic development in Muslim countries and communities, has ramped up its development efforts after it more than tripled its authorised capital in 2012.

With a combined $750 million in commitments from the three countries, the fund is targeting a final closing for early next year, the AAA-rated IDB said in a statement late on Thursday.

That surpasses the $730 million fund launched in 2001, which invested in firms such as Malaysia's AirAsia and Saudi International Petrochemical Co.

The new fund would mobilise up to $24 billion of aggregate financing to support development of key infrastructure projects in member countries, said IDB president Ahmad Mohamed Ali.

Newly-formed ASMA Capital Partners will manage the IDB fund, a Bahrain-based asset management firm owned by the IDB and the three sovereigns through their pension funds and finance ministries.

On Monday, the IDB approved $447 million in financing for development projects in member countries, including $220 million for a power grid extension in Bangladesh and $83.8 million for a power project in Uganda.

Energy, transport, water and sanitation projects make up about two-thirds of the IDB's lending portfolio. – Reuters