The best solution is a distribution of wealth somewhere in between. Say that the poorest will at least be able to affort a shelter, three meals a day, some creature comforts, education for their kids. I think most countries should be able to achieve this. In Singapore's case, deduct some expense from defence spending, should take care of it. But will the Ministry agree to this?
No one but the arch communist will advocate getting rid of rich people. In every society, some will be richer, some poorer, because of individual differences in talent, drive, priorities, luck, etc. That's as it should be.
What the UN is aiming for is eradicating abject poverty, where people live on less than US$2 a day and guaranteeing a minimum wage so that the
4 basic human needs are met: food, shelter over one's head, education, healthcare.
A society that has its Warren Buffetts and Li Ka-Shings should not tolerate anyone sleeping on the streets, starving to death, dying of illness because he/she is too poor to see a doctor, or children quitting school at the age of 12 to work to support the family.
Minimum wage on its own has its limitations. It has to be combined with basic social safety nets, compulsory education, universal health care, policies ensuring equality of opportunity and eliminating barriers to social mobility.