Pol Pot had friendly relations with the PRC since the 50s under Mao and had made many visits to receive military and political training. A 1975 conversation record of Chairman Mao Zedong's meeting with Pol Pot, Secretary of the Central Committee of the Communist Party of Kampuchea:

Pol Pot: We are very glad to do so, we are very happy to meet the Chairman.

Chairman Mao: Your fighting, WAR, political, military, economic, foreign policies and the united front–I won’t talk about it. I agree with what he says, he said you were right.

Pol Pot: Thank you. It warms our hearts to hear the Chairman say so.

Chairman Mao: We approve of what you do. Much of your experience is better than ours. China is not qualified to criticize you. We committed errors of the political lines for ten times in fifty years—some are national, some are regional (The mistakes made by) Chen Duxiu, Qu Qiubai, Li Lisan, and Luo Zhanglong had nothing to do with the Soviet Union. (Those made by) Wang Ming, Zhang Guotao, Gao Gang, Peng Dehuai, Liu Shaoqi, and Lin Biao involved the Soviet Union. They opposed us and divided the party, but they all failed. The party remained undivided and they were excluded. Thus I say that China has no qualification to criticize you, and can only agree with you. You are basically correct. I am not sure whether you have any shortcoming. There are bound to some and you’ll rectify by yourself. RECTIFICATION.I won’t talk about all these. Let this fellow surnamed Deng do it.

There is one point I’d like to talk about. Currently you are on the transition from democratic revolution to the socialist way. SOCIALIST WAY. There are two possible outcomes: one is socialism, the other is capitalism. We are still struggling between the two possible outcomes now. Wang Ming, Zhang Guotao, Gao Gang, Peng Dehuai, Liu Shaoqi, and Lin Biao—they wanted to build capitalism. In the next 50 or 100 years, there will still be a struggle between these two lines. In the next ten thousand years, there will still be a struggle between the two. Even when Communism is achieved, there will still be a struggle between the two. Otherwise we aren’t Marxists. The unity of opposites, UNITY OF OPPOSITES. If we only talk about one, that’s metaphysics; if we talk about two, then it’s the UNITY OF OPPOSITES, STRUGGLE OF OPPOSITES. I believe in what Marx and Lenin said.

The road is winding. Lenin’s Soviet Union changed under Khrushchev and Brezhnev. In future, it will still return to the Lenin’s path. The same goes for China. It could become revisionist in the future, but eventually it will follow the path set by Marx and Lenin.

We are now a capitalist country without capitalists, as said by Lenin. This country wants to protect the legal rights of the capitalist classes. People’s wages are not equal. It perpetuates unequal systems under the guise of slogans of egalitarianism. That’s what we are like right now and this will continue for many years before we achieve Communism. Communism will also have two lines of struggle, and the struggles between the progressive and the backward. We can’t talk about it comprehensively as yet. These are what we openly say in the newspapers. That’s all I have to say.

Pol Pot: We are very honored to be able to pay our respects to Chairman Mao here today. We have always respected Chairman Mao and learned from your works. Your writings have guided our revolution until we achieved a nationwide victory. We are able to meet Chairman Mao in person today and hear Chairman Mao talk about the issue of the lines. This is a very important and strategic issue. We will be sure to do as you say from now on. I studied many of Chairman Mao’s works from a young age, particularly your work on the people’s war. Chairman Mao’s works guided our entire party while we were engaged in the political and military struggles. We made use of it in our actual struggle and achieved results. When our struggles entered the most difficult stage , we studied the work The Struggle in the Jinggang Mountains, and it steeled our resolve. We also paid close attention to the experience of the Chinese people led by Chairman Mao after China was liberated. We read articles talking about China’s experience very closely. Chairman Mao’s earlier comments on the issue of the line struggle...

Chairman Mao: Uh huh.

Pol Pot: We also study it within the party. We pay close attention to class struggle and line struggle. We will study and learn from the experience of China until we achieve the final victory.

Chairman Mao: Don’t copy China’s example completely. Master Shi said, whoever attempts to be like me will get sick. Master Shi is named Kumarajiva, living during the ear of the Southern and Northern Dynasties. He was a foreigner who could speak Chinese and he translated many Buddhist texts. We have to figure it out on our own. As Marx said, their teachings could only serve a guide and are not doctrines. Marx said so himself. Kumarajiva’s words were quoted by a Chinese scholar called Yan Fu . Yan was a translator. This quotation is from (the introduction of) On Evolution translated by Yan. Yan said he was not “translating”, but was “expressing the original texts elegantly,” and that was what was he did for this book. But he translated literally the other works such as those about political economies. This was written by (Thomas Henry) Huxley, HUXLEY . He was British and a supporter of Darwin and called himself “Darwin’s Bulldog.” He came up with the idea of “agnosticism., German Kant talked about agnosticism. Huxley said the agnosticism talked about by Kant, only knew what was on the surface but not the substance. He was a materialist in his understanding of the natural sciences and idealist with regards to the social sciences. He endorsed Indian Buddhist philosophy. Thus Marx called him a “shamefaced materialist.” I’ve never said so much to other people on the things I’ve said to you.

Pol Pot: Thank you. This is a great honor to us. Chairman Mao has received us today and talked to us about so many things and given us a great deal of inspiration. It is a treasure trove for our party and people. Please allow us to express our deepest thanks once again.

Chairman Mao: Don’t thank me. Thank Marx and Lenin. There are 30 works of Marx, Engels, Lenin and Stalin, in big type, that I wish to gift to you. Marx and Lenin said it very well, better than myself.

Pol Pot: We are glad to receive them. We will study them very hard and apply them in accordance with the conditions in our country. We also want to continue learning Chairman Mao’s works. Chairman Mao: I am not satisfied with myself. Alright, thank you!

Pol Pot: We are taking our leave. I wish Chairman Mao a long life! I represent our delegation, our party and all our fighters in wishing Chairman Mao longevity! Farewell!

Chairman Mao: Thank you.

Pol Pot: Goodbye!