Speaking on Friday morning, Second Rear Admiral Gholamreza Tahani said the drills will begin with the three countries' vessels leaving Iran's Chabahar port in the Gulf of Oman and deploying across the northern areas of the Indian Ocean.
The drills, dubbed the "Marine Security Belt" exercise, will cover 17,000 square kilometers and consist of "various tactical exercises" such as target practicing and rescuing ships from assault and incidents such as fires, Tahani said.
"َAmong the objectives of this exercise are improving the security of international maritime trade, countering maritime piracy and terrorism, exchanging information regarding rescue operations and operational and tactical experience," he added.
Speaking about the significance of the drills, Tahani said the Indian Ocean is the world's third largest ocean which neighbors many countries and incorporates the strategic straits of Hormuz, Malacca and Bab el-Mandeb.
Message of drills
“The message of this exercise is peace, friendship and lasting security through cooperation and unity... and its result will be to show that Iran cannot be isolated,” Tahani said on state television.
According to reports, Iran is taking part in the maneuvers with its Sahand and Alborz destroyers, the Konarak and Tonb logistic warships, the Neyzeh missile boat and the Nazeri hospital ship.
On Thursday, Chinese Defense Ministry spokesman Wu Qian announced that Beijing's Xining guided-missile destroyer will take part in the drills, which it called a “normal military exchange” between the three armed forces.
“It is not necessarily connected with the regional situation,” a Chinese Defense Ministry spokesman said.
China has close diplomatic, trade and energy ties with Iran, which has friendly ties with Russia.
Russia's Defense Ministry said on Friday it had sent three ships from its Baltic Fleet – Yaroslav Mudry frigate, Yevgeniy Khorov tanker and Yel'nya rescue tug boat – to take part in the drills, Red Star, the official newspaper of Russia's armed forces, reported.
The ministry was quoted as saying that it was the first time that such drills were being held in such a format.
Speaking on Friday, Tahani said that one of the most important achievements of the drills are the message that Iran "cannot be isolated".
The joint drills, he said, signal that relations between Tehran, Moscow and Beijing had reached a "meaningful" level and that such a trend will continue in the future.
"This is the first time following the Islamic Revolution (of 1979) that Iran has held a joint maneuver with two major global naval powers at this scale," he said.
"Surely countries that are closer to each other in economic, political, social, defense and security-related fields cooperate together to ensure their collective security," he added.
Also on Friday, Mojtaba Zolnour, head of the Iranian Parliament's National Security and Foreign Policy committee, hailed the drills as indication of Iran's success in multilateral military cooperation despite US attempts to isolate it.
Failed US diplomacy
Zolnour added that Washington had failed at its "military diplomacy" and that it will grow weaker in the future.
"Holding a joint exercise between Iran, China and Russia is a very terrifying measure for the US and the West which seek to create a military coalition against the Islamic Republic of Iran," he said.
Iran's joint drills with the Chinese and Russian forces come amid the United States’ ongoing efforts to pressure and isolate Tehran by coupling robust sanctions and regional military deployments as part of a campaign of "maximum pressure".
Earlier this year, Washington announced that it was seeking to form a maritime coalition patrolling the Persian Gulf after blaming Iran for a series of suspicious attacks on passing tankers in the waterway, which Tehran has described as "false flag" operations.
The United States used the attacks as a pretext to send additional troops and warships to the Persian Gulf, citing unspecified Iranian threats.
The coalition has, however, received a lukewarm welcome from US advocates and only a few Washington allies, including Saudi Arabia and Bahrain joined it.
Amid Washington's bolstered regional deployments and military provocations targeting Tehran, Iran shot down an American spy drone for violating its airspace near the Strait of Hormuz in June.
Press TV and Reuters contributed to this story.