MNA � First Vice President Es�hagh Jahangiri said that development of rail lines is put atop agenda of the government and plans have been made to connect all provinces' capitals to the rail line system.

He made the remarks during the inauguration of the 4th line of Mashhad's subway system on Friday.

�Rail lines are considered as the safest and cheapest transport system in the country; thus, the government has made every effort to equip rail line system in the country using the most modern equipment and technology.�

Development of the subway systems has currently been put atop agenda of the government in nine metropolises of the country, he said and added, �construction of subway lines, as long as 70 km, is underway nationwide.�

He went on to say that the construction of Tehran-Qom-Isfahan High-Speed Train is also underway.

Jahangiri put the investment volume needed for launching Tehran-Qom-Isfahan High-Speed Train at $5 billion.