Critics at home and abroad have condemned the "anti-coronavirus defence law", saying it gives Orban unnecessary and unlimited power in a ruse to cement his leadership rather than battle the virus.
Orban's government proposed the bill to parliament earlier this month to enable wide rule-by-decree powers to tackle the virus under an extended state of emergency.
According to the draft posted on the parliament website on March 20, the bill would enable the government to indefinitely extend the state of emergency and its associated powers of rule by decree, removing the current requirement for MPs to approve any extension.
It also introduces jail terms of up to five years for anyone spreading "fake news" about the virus or the measures against it, stoking new worries for press freedom.
Since taking power in 2010, the self-styled "illiberal" nationalist has transformed Hungary's political, judicial and constitutional landscape.
The 56-year-old has frequently clashed with European institutions, NGOs and rights groups with Brussels suing Hungary for "breaching" EU values -- charges fiercely denied by Budapest.
Orban has given criticism of the law short shrift, appealing to "European moaners" to let Hungary defend itself against the virus.
His justice minister, Judit Varga, told foreign reporters in a briefing on Friday that critics of the bill were "fighting imaginary demons and not dealing with reality".
Opposition MPs last week refused to let the government fast-track the bill through parliament.
But it is almost certain to be made law when it comes before MPs on Monday as Orban's Fidesz party enjoys a two-thirds majority.
'Principles of democracy'
Agnes Kunhalmi, a lawmaker for socialist opposition party MSZP, urged Orban to "not perpetrate political games against the opposition" and add an expiration date to the bill.
"There is concern that the government will continue its conservative-liberal practices, which will lead to an even deeper crisis," she told AFP.
Akos Hadhazy, an independent MP, told AFP that Orban did not need any "extraordinary empowerment" as his party already controls parliament and had instead set up a "trap for the opposition" with pro-government media accusing it of being on the side of the virus by opposing the bill.
"Parliament is just a machine to vote anything he wants," he said.
Criticism of the bill has also come from abroad with the UN human rights office saying it was following the Hungarian developments "with concern".
The Council of Europe also wrote a letter to Orban last week, warning that an "indefinite and uncontrolled state of emergency cannot guarantee that the basic principles of democracy will be observed."
Hungary ordered a state of emergency on March 11 as part of protective measures aimed at stemming the spread of the COVID-19 virus, which have included the closure of borders to non-national passenger traffic.
The EU member state of 10 million has so far reported more than 400 confirmed coronavirus cases with 13 deaths. More than 12,100 tests have been carried out, the government said Sunday.
The fiercely anti-immigration Orban has blamed migration for the spread of the virus, saying "primarily foreigners brought in the disease".
Orban's latest move will also strain already difficult relations between Fidesz and the European Parliament's conservative EPP grouping which has dithered over expelling the party from their ranks.
Austrian-Hungarian author Paul Lendvai has said the system installed by Orban has been "so far seen as a 'hybrid state', neither democracy nor dictatorship," and asked whether the new powers could turn Hungary into "the EU's first dictatorship".
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