According to documents recently released by the State Department, Chairman Mao tried to solve China's population problem in 1973 by offering Chinese women to US envoy Henry Kissinger:
"You know, China is a very poor country," Mao is quoted as saying during the exchange. "We don't have much. What we have in excess is women. So if you want them we can give a few of those to you, some tens of thousands."
The Chinese leader drew laughter when he returned to the proposition a few minutes later. "Do you want our Chinese women? We can give you 10 million." he said, adding: "We have too many women ... They give birth to children and our children are too many."
Kissinger, ever the diplomat, demurred: "It is such a novel proposition, we will have to study it."
Link - via FP Passport
It was clearly a joke - he was teasing the women interpreters.