WASHINGTON - Singapore's upcoming Cabinet reshuffle is likely to take place in early June, Prime Minister Lee Hsien Loong said.

The move is likely to see Finance Minister Lawrence Wong, PM Lee's successor, promoted to deputy prime minister.

PM Lee said the Cabinet changes were in the works and added that he expected them to be announced after his upcoming overseas trips.

He is scheduled to speak at the 27th International Conference on the Future of Asia on May 26 and 27, organised by the Nikkei business media group. The conference, titled "Redefining Asia's role in a divided world", will be streamed online and held in Tokyo.

"I am working at it. I had to focus on this trip, and I have another trip coming up in two weeks' time, going to the Nikkei conference," said PM Lee on Friday (May 13, US time). He had been asked by Singapore reporters for updates on Cabinet movements.

"But I am working at it and hope I shall be able to do it once I am done with my trips, which means early June," he added.

PM Lee was speaking after the Asean-United States Special Summit in Washington, which ended on Friday. He leaves Washington on Saturday.

Last month, Mr Wong was announced as the top choice of Singapore's fourth-generation team of political leaders to head them, paving the way for him to be the country's next prime minister.