Macau's former top court judge, Sam Hou-fai, on Wednesday formally declared his intention to run for the post of chief executive in the SAR.

On Monday, Sam resigned as president of the Court of Final Appeal to pave the way for his leadership bid.

Speaking at the Macau Science Centre, Sam said if elected, he would firmly implement the principle of "One Country, Two Systems" and make government more efficient.

He also vowed to safeguard Macau's long-term stability and prosperity, and create a better future for the gambling hub.

"The international environment has been changing and developing rapidly. In the past few years, it has brought challenges to the development of our country, and to our small special administrative region, the Macau SAR," he told reporters.

"We must reform and innovate to solve the difficulties in the development process, and mitigate the negative effects of some development bottlenecks."

Sam said he will start getting in touch with the 400 election committee members on Thursday, when nominations open.

Hopefuls need to secure at least 66 nominations in order to run in the poll slated for October 13.

Responding to reporters' questions in Portuguese, Sam also pledged to preserve the Macanese culture and the Portuguese language.

"Over the past 25 years since the handover, the Macanese community has actively participated in various fields such as politics, economy, culture, professional sectors, and education in Macau. They have made important contributions to the successful implementation and development of 'One Country, Two Systems' with unique characteristics in our SAR," he said.

"These contributions are evident for everyone. The Macanese community, including the Macanese people and the Portuguese language as an official language, is a distinctive and important feature of our Macau SAR that's not found elsewhere."

Sam, 62, became a lawyer on the mainland before moving to Macau in 1986. He went to Portugal to study in 1990 and returned to the casino hub three years later.

He became a judge in 1997 and was appointed president of Macau's Court of Final Appeal in 1999.

He tried major cases during his tenure, including the corruption trial of former transport and public works chief Ao Man-long, who was sentenced to 29 years in prison.

If elected, Sam would be the first Macau CE without a business background.