Prime Minister Najib Razak took a fresh swipe at his one-time mentor, this time over Tun Dr Mahathir Mohamad's often confrontational foreign policy approach when he was Malaysia's leader for 22 years.

Without naming the former premier, Datuk Seri Najib said that "for decades we had a leader who adopted intentionally confrontational foreign policy positions, perhaps for personal popularity".

"When I became Prime Minister, I chose to be different, and make a clear break with past approaches," Mr Najib said at the opening of the biennial conference of the Commonwealth Association for Public Administration and Management yesterday. "No more insisting on awakening old quarrels or harping on old slights," he said. "Instead, I decided that national interest should always come before personal political interest."

Mr Najib said his leadership has focused on developing economic partnerships with other countries that would be beneficial to Malaysians. He cited Malaysia's improved ties with Singapore. "I have worked to deal with legacy issues with Singapore, for example, and our resolution of the Points of Agreement in 2010 after a 20-year deadlock is a good case in point," he said.

In 1990, both countries reached an agreement, known as the Points of Agreement, to move Malayan Railways' station from Tanjong Pagar to Woodlands.

But the move was held up over differing interpretations of seve- ral clauses until 2010, when a historic land-swop deal between Mr Najib and his Singapore counterpart Lee Hsien Loong broke the 20-year impasse.

Mr Najib yesterday also praised the two countries' "spirit of friendship", which saw the signing of a memorandum of understanding last month for a high-speed rail project, which will slash travel time between Kuala Lumpur and Singapore when it is completed.

During his tenure as prime minister, Dr Mahathir was known for his strong stance against the West, pushing the country to "Look East" and initiating mega infrastructure projects to fuel nationalistic sentiments.

In the past two years, he has directed his firepower at Mr Najib, criticising the Prime Minister's governance and also his handling of the 1Malaysia Development Berhad (1MDB) financial scandal. Mr Najib is also Finance Minister and his ministry owns 1MDB. He headed the state fund's advisory board until its dissolution in May.

Mr Najib has faced tremendous pressure from Western media over the 1MDB scandal. More recently, the US Department of Justice filed a civil suit to seize more than US$1 billion (S$1.34 billion) in assets that are tied to 1MDB.

In his address to an international audience, Mr Najib reiterated his stance against foreign intervention, reminding the world to respect a government's right to manage its own business.

The days when "imperial powers could tell others how to behave, whether politically, economically or culturally, are over", he said.