The Philippine government has sought a loan from Asian Infrastructure Investment Bank (AIIB) to finance the Manila Metro Rail Transit Line 4 (MRT-4) project.

The AIIB is considering providing a loan of US$537.4 million for the MRT-4, which has a total value of US$1.792 billion. The first phase of the project is a joint effort between the AIIB and the Asian Development Bank (ADB). The program aims to construct a high-capacity railway mass transit system, serving the eastern side of Metro Manila from the EDSA-Ortigas Ave. Junction to Taytay in Rizal Province (MRT4 Line). The system will consist of a 12.7 km elevated viaduct with 10 stations, designed to be barrier-free and inclusive for all.

The MRT-4 will reduce the travel time from Taytay to the Ortigas central business district to less than half an hour via rail. Once fully operational by 2028, the project is expected to serve more than 400,000 passengers daily.