Prime Minister Tunku Abdul Rahman made a speech suggesting rising tension between Kuala Lumpur and Singapore, which was then part of the new nation Malaysia.
Speaking at a convention of the ruling Alliance coalition - which comprised Umno, the Malaysian Chinese Association and the Malaysian Indian Congress - he warned that Singapore was trying to usurp the authority of the central government.
He said Singapore Prime Minister Lee Kuan Yew's remarks, after a recent trip to Australia and New Zealand, showed that the People's Action Party (PAP) - which ran the state government in Singapore - wanted a say in running the central government.
"We dreamt of Singapore in connection to Malaya as what New York is to America, but little did we realise what the leader of the PAP had in his mind was a share in the running of Malaysia," the Tunku said.
Mr Lee, who went on a month-long official visit to New Zealand and Australia from March to April, had made the case that it was important for them to help defend Malaysia against Indonesia and impressed the media in the two countries.
But his comments against communalist rule in Malaysia also drew flak from Kuala Lumpur.
In a speech at the University of Western Australia in Perth, Mr Lee said the problem facing Malaysia was devising "a formula to ensure that the authority that ultimately emerges in Malaysia is one that will command the loyalty, the support of the majority of all the various racial, linguistic groups in the country".
"You see, there is no other way, because no one single linguistic or racial group is in a position to enforce its will on the others... The price that any communalist must pay if he wants to assert the supremacy of any linguistic or racial group is conflict that must lead to disintegration," he said.
His detractors accused him of bad-mouthing Kuala Lumpur and promoting himself during the trip.
Federal Minister of Education Khir Johari said he had received a number of letters from Malaysian students in Australia and New Zealand saying Mr Lee had distorted the country's image on his trip.
Mr Lee told a press conference after his trip that he stood by every speech he made while on his visit. He had not gone to Australia to make his own point against that of any other political party or in favour of his own party. It would have been foolish of him to do so, he said.
The Australians and New Zealanders were not interested in supporting the People's Action Party or Umno, but interested in Malaysia. "In spite of our present difficulties I think Malaysia is a winner, provided everybody understands what the problems are and is prepared to accommodate each other."
A few days after his return, Umno secretary-general Ja'afar Albar accused Singapore leaders of trying to "stab the central government in the back".
In his speech at the Alliance meeting, the Tunku said Singapore's entry to the Federation of Malaysia had been crucial to the well-being of Malaysia because Singapore was in danger of being taken over by Communists at one point, and that would have caused chaos in the region.
He had hoped the PAP would co-operate to make the whole of Malaysia safe for its people but Mr Lee took "our refusal to let him have a share in the running of the central government as a challenge". This was unacceptable since the Alliance was strong enough to run the country on its own, he said.
"Whatever party is returned to power by the will of the people, that party is considered as the one which enjoys the confidence of the people and, as such, it must accept the duties and responsibilities of running the government," the Tunku said.
Mr Lee later wrote in his memoirs that he had hoped that Australian Prime Minister Robert Menzies could help influence the Tunku to find a solution for the divisions troubling Malaysia.
This article was first published on Apr 12, 2015.
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