From North Korea to China to Russia, it appears everyone is gearing up for another world war.

The latest to join in the preparation is Iran.

The Middle East country is said to have completed its third underground ballistic missile production factory and will keep developing its missile programmes, according to the semi-official Fars news agency.

Fars quoted the head of the Republican Guard’s airspace division, Amirali Hajizadeh, as saying, “Iran’s third underground factory has been built by the Guards in recent years. We will continue to further develop our missile capabilities forcefully.”

Since taking office in January, U.S. President Donald Trump has imposed new sanctions on Iran in response to Tehran’s recent missile launches, putting Tehran “on notice”.

Iran’s Sunni Gulf neighbours and its arch-enemy Israel have expressed concerns over Tehran’s ballistic missile programme, seeing it as a threat to regional security.

“It is natural that our enemies America and the Zionist regime (Israel) are angry with our missile program because they want Iran to be in a weak position,” Hajizadeh said.

In retaliation for the new U.S. sanctions, Iran had added nine American individuals and companies to its own list of 15 U.S. companies for alleged human rights violations and cooperation with Israel.