SINGAPORE - Prime Minister Lee Hsien Loong has emphasised the importance of further enhancing Singapore's relationship with the US, as he arrived in Washington for a working visit on Saturday (Oct 21).

"Singapore and the US have a long history of cooperation. Our people do too, with many working, living, and thriving in each other's countries," he wrote in a Facebook post on Sunday morning (Singapore time).

"We are close, so it is important to keep growing our relationship."

He also shared a photo of the Singapore flag hanging over the historic Blair House, a sight which he said lifted his spirits despite the long flight.

It will be PM Lee's third time staying at the President's Guest House, which he described as "an honour".

Built in 1824, the house has hosted other notable world leaders such as former British Prime Minister Margaret Thatcher, former French president Charles de Gaulle, Japan's Emperor Akihito, Russian President Vladimir Putin and India's Prime Minister Narendra Modi.

PM Lee's official working visit to Washington is at the invitation of US President Donald Trump, whom he will meet on Monday.

During his six-day visit, PM Lee will also meet key administration officials as well as members of the Congressional leadership.

He will also participate in a moderated dialogue at the Council of Foreign Relations (CFR) and speak at the Economic Club of Washington DC.