China and Iran have expanded their diplomatic ties to the level of a global strategic partnership against the West with the signing of a landmark 25-year comprehensive cooperation agreement on Saturday.

The new strategic accord, which was set into motion in 2016, encompasses military, economic and political issues. It was signed by Chinese Foreign Minister Wang Yi and his Iranian counterpart Mohammad Javad Zarif and seeks to strengthen China's and Iran's long-standing economic and political alliance.

Wang is on a six-day diplomatic foray to visit six of China's Middle East allies, including Iran.

The agreement will see an increase in bilateral trade by more than 10-fold to $600 billion over the next decade. No details of the agreement were made public, but the deal is expected to include significant Chinese investments in Iran's key sectors such as energy and infrastructure, and more military cooperation.

The accord also firmly enmeshes Iran in China's Belt and Road Initiative, a multi-trillion global infrastructure development strategy launched in 2013 that has seen China invest in nearly 70 countries and international organizations. BRI will significantly expand China's global economic and political influence, and is a huge problem for the United States.

Zarif praised China for standing-up for Iran against the U.S., calling China "a friend for hard times."

"The signing of the comprehensive cooperation program of the Islamic Republic of Iran and the People's Republic of China by the foreign ministers of the two countries is another program of this two-day trip," noted state news agency IRNA.

Iranian foreign ministry spokesman Saeed Khatibzadeh said the accord "is a complete roadmap with strategic political and economic clauses covering trade, economic and transportation cooperation ... with a special focus on the private sectors of the two sides."

Wang praised Iran for its defiance of the West, especially for enduring the sanctions, which were bolstered when former president Donald Trump withdrew the U.S. from the Joint Comprehensive Plan of Action, or the Iran nuclear deal.

"Our relations with Iran will not be affected by the current situation, but will be permanent and strategic," said Wang, referring to the sanctions levied by the West, especially the United States, on Iran.

"Iran decides independently on its relations with other countries and is not like some countries that change their position with one phone call."

Wang also met with President Hassan Rouhani and Ali Larijani, a representative of the Supreme Leader Ali Hosseini Khamenei, who is said to have been the point person on the 25-year accord.