Guangdong and Hong Kong are "brothers", and the two complement each other economically, Chief Executive Leung Chun-ying said on Wednesday.
Leung, who was visiting Guangdong's new Communist Party chief Hu Chunhua , thanked the provincial government for its support in Hong Kong's crackdown on parallel-goods traders and mainland mothers giving birth in the city.
"[The Guangdong government] has given the SAR government great support when it comes to cracking down on the illegal parallel trading and pregnant mainland women giving birth in Hong Kong," said the chief executive.
Leung added that he had wanted to pay Hu a visit right after he took on the Guangdong chief role in December, but had been busy preparing for his policy address.
Hu said the two places' close relationship was a great advantage for Guangdong's development, which had in fact been fostered by the people, financial resources and techniques from Hong Kong.
"The co-operation between Guangdong and Hong Kong benefits Guangdong and also helps to make Hong Kong prosperous and stable," he said.
Co-operation between the two places have deepened recently, Hu said, citing the Qianhai development as an example.
In another meeting with Shenzhen party chief Wang Rong and mayor Xu Qin later in the day, Leung also thanked the Shenzhen municipal government for its help in the action against parallel-goods trading and mainlanders giving birth in Hong Kong.
Wang said he had noticed the SAR government's efforts to beef up environmental protection, and that he hoped for more co-operation between Shenzhen and Hong Kong on the matter.