The right-wing nationalist particularly opposes immigration by Muslims.
About 2,000 people gathered in front of his office, while others blocked one of the main bridges across the Danube river.
Correspondents say the biggest applause during Mr Orban‘s speech was for his announcement of a seven-point plan to increase the birth rate.
Increasing birth rate ‘very difficult‘
The ‘s Nick Thorpe in Budapest writes:
Critics of the government say its package and pro-family policy so far target well-off families and ignore the Hungarian poor, including an estimated 750,000 Roma (Gypsies). Tax relief does little to help families who pay little tax anyway.
About 600,000 Hungarians have moved to western Europe in the past decade – it is impossible to calculate how many will return.
“Increasing the number of births is very difficult, because we have less and less women of child-bearing age,” State Secretary for Families Katalin Novak told the . That number is set to fall by 20% in the next decade. “So less and less women need to have more and more babies.”
The government‘s new package, she emphasised, is based on the number of babies couples would actually like to have, and then to encourage them with financial help. The aim is to increase the fertility rate to 2.1 by 2030.
How do other countries help mothers?
Many other countries with relatively low birth rates have introduced extra payments and other benefits for mothers.
Russia‘s birth rate has been declining for decades: the population fell from 149m in 1991 to 140m in 2018, and the median age has risen from 33 to 39.
So, to help the poorest families, in March 2018 the government announced monthly payments of 10-11,000 roubles (£118-£130; $152-$167) until their first child reached 18 months old. A poor family also gets a one-off payment of 300,000 roubles for each additional child born.
Last March it announced that new mothers would get a one-off payment worth £740 ($956) for their first child, monthly payments of £74 ($96) for the second child for two years, and further payments for three or more children.
The birth rate in Italy is among Europe‘s lowest, along with Cyprus and Spain. Italy gives mothers an allowance of €80 per month (£70; $90) for each child born. The poorest families get a monthly allowance of €160 per child.
In Germany more babies were born in 2016 than in any year since 1996. But Germany has also put more incentives in place for couples to have children. Parents have a legal right to a nursery place once their child is one year old.
Germany has a new law, the “Good KiTa Act”, granting lower childcare fees for parents who cannot afford the full price, and a fee exemption for parents who receive a child allowance and housing benefits.
Low birth rates are also worrying governments in East Asia.
According to World Bank data for 2016, just a few countries, including Singapore and Moldova, have a fertility rate as low as South Korea‘s – 1.2 per woman. The replacement rate – the number needed for a population to remain level – is 2.1.
Fertility rates are also low in China (1.6) and Japan (1.4).
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