The formal test run of the country's first metro rail service will start from today when a metro train will run on the elevated rail track connecting the depot in the capital's Diabari and the first four stations.

The test run in the Uttara North, Uttara Centre, Uttara South and Pallabi stations will be inaugurated by Obaidul Quader, the road transport and bridges minister, at the depot at 10:00 am today.

On Friday, as part of the preparation, the authorities operated the train between four stations at a very slow speed to check safety issues and take different technical measurements ahead of today's programme, said ABM Arifur Rahman, project manager (CP-8) of Mass Rapid Transit Line-1 project.

A fifth station at Mirpur-11 will also be kept ready today as when the train reaches the Pallabi station it will get power from the power sub-station at Mirpur-11.

After the performance test, the authority would move on to integrity tests for synchronisation and then on to trial run.

Dhaka city dwellers, however, may have to wait more than a year to ride the metro train because of the host of testing required to be eligible for commercial operation.

Citing the experience of different countries, MAN Siddique on May 11 told the newspaper that it takes six months to a year or even more in some cases to complete all tests.

After completion of all tests, the authorities will go for a trial run before launching the commercial service. The trial run may take up to 10 weeks, he said.

The authorities have a plan to make at least the first stretch from Uttara to Agargaon of the 20.10-kilometre metro rail line operational by December next year.

The original implementation period of the Tk 21,985 crore project was 2012-2024.

Prime Minister Sheikh Hasina later directed that metro services from Uttara to Agargaon be made operational by 2019, and from Agargaon to Motijheel by 2020.

Failing to meet the deadline, the authorities in May 2019 said the services would be launched on December 16 this year as the country celebrates the golden jubilee of its independence.

But Finance Minister AHM Mustafa Kamal in his budget speech on June 3 this year said activities were underway to start passenger transport in the Uttara-Agargaon section of the metro rail by December 2022.

When the correspondent asked Siddique about the deadline on Thursday, he said the road transport and bridges minister would reveal the information formally.

Once complete, the metro rail -- with 16 stations -- will be able to carry 60,000 people an hour, bringing down the travel time from Uttara to Motijheel to around 40 minutes. The journey now takes about two hours on a regular day.

The first set of metro trains reached Dhaka on April 21 and the depot two days later, marking a major development in the project.

Bangladesh's first ever electric train was rolled out on the tracks on a test run inside the depot in the city's Diabari on May 11. Since then, the authorities have been conducting performance tests inside the depot.

Meanwhile, as per the prime minister's instruction, the authority decided to extend the metro rail from Motijheel to Kamalapur. However, the physical work of the portion has not started yet.