Chinese President Xi Jinping will pay a state visit to the United States from Sept. 22 to 25 to meet with U.S. President Barack Obama. He will also attend a series of summits to commemorate the 70th anniversary of the establishment of the United Nations from Sept. 26 to 28.

Xi and Obama's meeting will be put in the spotlight soon. But before that, let's look back to the five memorable moments when they met concerning diplomatic ties between the two countries.

Moment 1: Annenberg walk, diplomacy without neckties

Chinese President Xi Jinping meets with President Barack Obama for the second time on the morning of June 8, 2013 at The Annenberg Retreat at Sunnylands in Rancho Mirage, California. [Photo/Xinhua]

Time: June 7 - 8, 2013

Location: Annenberg Retreat, California, the United States

Memories: In June of 2013, President Xi was traveling to Latin America for a visit and then visited the United States at his leisure. He met with President Obama at the Annenberg Retreat in California in a relaxed setting. This was neither a working visit nor a state visit. So there was no welcome ceremony, no 21-gun salute, and no tie wearing.

Xi and Obama had two meetings, one private dinner and one walk together. The two leaders had personal communication and exchange for a total of 8 hours. They reached a series of important consensuses and gained positive achievements regarding the building of a new pattern of relations between two major countries of China and America, as well as bilateral cooperation and other international and regional issues.

Xi said Sino-U.S. relations were standing at a new starting point while Obama said it was a unique opportunity to take the relationship of two countries to a new level.

"Retreat meeting" became a new model for Chinese and American leaders.

Moment 2: Xi is given a California redwood bench as a gift

U.S. President Obama sits with President Xi on a gift bench made out of California redwood before their second meeting on the morning of June 8, 2013 at The Annenberg Retreat at Sunnylands in Rancho Mirage, California. [Photo/Xinhua]

Time: June 7 - 8, 2013

Location: Annenberg Retreat, California, the United States

Memories: President Obama presented President Xi with a gift of a bench made out of California redwood before the second meeting when they walked together for relaxation on the morning of June 8, 2013 at the Annenberg Retreat at Sunnylands estate in California. The redwood is a precious wood in California. In 1972, former U.S. President Richard Nixon visited China and brought several saplings of California redwood to the Chinese people as a gift. From then on, the redwood tree has been introduced and planted into several provinces and cities in China as a symbol of Sino-U.S. friendship.

Moment 3: Two leaders attend the G20 summit

Chinese President Xi Jinping meets with U.S. President Barack Obama in St. Petersburg, Russia during the G20 summit on Sept. 6, 2013. [Photo / Xinhua]

Time: September 2013

Location: St. Petersburg, Russia

Memories: Three months after the meeting in the Annenberg Retreat, Xi met with Obama again in St. Petersburg, Russia.

Chinese President Xi Jinping hailed the progress in bilateral cooperation over those months as "fruitful" when meeting with U.S. President Barack Obama. "Since the Annenberg estate meeting, the two countries have closely collaborated with each other to implement the consensuses reached," Xi said.

“Currently, the China-U.S. relationship is maintaining a good momentum of development,” Xi said. He also introduced China's economic situation and stressed that China will maintain its reform and opening up policy which will offer more opportunities for China and U.S. cooperation.

Obama said they agreed to continue to build a new model of major-country relations based on a practical cooperation and to constructively mend differences, and added, "We welcome the peaceful rise of China."

The countries made progress on cooperation of climate change and the strengthening of military-to-military ties to ensure awareness and "avoid potential conflict and miscommunication", Obama said.

Moment 4: Obama, Xi summit at the Nuclear Security Summit

Chinese President Xi Jinping and U.S. President Barack Obama meet in The Hague, Netherlands on March 24, 2014 ahead of the Nuclear Security Summit. [Photo/ Xinhua]

Time: March 2014

Location: The Hague, Netherlands

Memories: Chinese President Xi Jinping met with U.S. President Barack Obama at the U.S. ambassador's residence in The Hague, Netherlands on March 24, 2014 ahead of the Nuclear Security Summit.

Xi Jinping stressed that 2014 marks the 35th anniversary of the establishment of China-U.S. diplomatic relations. Faced with the current complicated international situation, China and the U.S. enjoy broader areas of cooperation. The Chinese side is willing to work with the U.S. side to always adhere to the right course of establishing a new model of major-country relations and to promote bilateral relations for a constant, sound and stable development.

Obama expressed that, over the 35 years since the establishment of the diplomatic relationship, U.S.-China relations have made considerable progress. With increasingly close bilateral exchange and the interests of the two countries closely connected, U.S.-China relations have become one of the most important bilateral relations in modern times. He is willing to keep up communication with President Xi Jinping on a series of major issues, and jointly promote the establishment of a new model of U.S.-China major country relations. The U.S. has no intention to damage the stability in China or to contain China, and it supports the reform process in China. With regard to the differences and frictions existing between the two sides, the U.S. side is willing to handle these issues in a constructive manner. The U.S. is ready to work with China to send out the positive message that both sides are committed to developing U.S.-China relations.

Moment 5: Xi and Obama have late night talks in Beijing

Chinese President Xi Jinping and U.S. President Barack Obama meet in the evening at Yingtai, Zhongnanhai, the central government compound of China in Beijing, on Nov. 11, 2014. [Photo/ Xinhua]

Time: November 2014

Location: Zhongnanhai, Beijing, China

Memories: In the evening, Zhongnanhai saw rippling lake water and flickering tree shadows. Xi Jinping greeted Obama in front of Yingtai, and the two heads of state shook hands warmly and exchanged greetings. Xi Jinping welcomed Obama's attendance at the Asia-Pacific Economic Cooperation (APEC) Economic Leaders' Meeting in China and his state visit to China. Xi Jinping said to President Obama, “you have a tight schedule for this visit. We have arranged official events for the state visit as well as some relaxed occasions. I hope that you have a pleasant visit and achieve fruitful results.” Obama said that he was glad to pay a state visit to China again and congratulated China on their success in hosting the APEC Economic Leaders' Meeting.

On the Yingtai Bridge, the two heads of state leant on the railing overlooking the pavilions scattered under the glorious lights. Xi Jinping briefed Obama on the history of Yingtai, which has witnessed the vicissitudes of China for centuries. Xi Jinping said that knowing the modern history of China is of great importance to understanding the Chinese people's ideals today and their development path.

The two heads of state then walked up the steps and held a meeting at the Hanyuan Hall.