The phrase "adamantly demanding" is correct and usable in written English.
It can be used to describe someone who is firmly and resolutely insisting on something.
Example: "The protesters were adamantly demanding justice for the victims of the incident."
Alternatives: "firmly insisting" or "stubbornly requesting".
Many longtime observers expected hostilities to flare up in Abkhazia, whose separatist leaders have adamantly demanded independence.
It also more adamantly demands that advertisers have the consent of users whose email addresses or phone numbers they upload for Custom Audience targeting, though Facebook does little to verify that consent and advertisers could still buy data sets from brokers and upload them themselves.
Kurds, equally adamantly, are demanding that the United States back off its own position.
Just two years ago, Britain and the United States were demanding adamantly that the two suspects be tried in Scotland, the site of the crime.
He was adamantly opposed to demanding proof of income and to handing out boxes of food packed according to a committee's idea of health.
Mr Cazenueve has adamantly rejected demands from Ms Bouchart, the Calais mayor, for the creation of a new shelter outside the port to take migrants off the streets.
So Bush pushed back, and demanded that the timetable end one day before 2012 started (far enough out, he thought, for nobody to notice that it was what Obama was demanding and what Bush adamantly refused to back).
Manufacturing executives adamantly rejected the demand, and they do not plan to discuss new ideas until at least next week.
But it is worth noting that even as Mr. Gonzalez demanded his son's speedy return, he adamantly rejected the quickest way to achieve it -- namely, going to the United States himself -- until last week when the regime itself proposed that course.
Even as the US administration and the international community have moved into dialogue with Iran in recent weeks, in response to the election of the more moderate President Hassan Rouhani, Mr Netanyahu has been adamantly insisting that Tehran remains bent on acquiring a bomb and demanded that it fully dismantle its uranium enrichment capabilities as a precondition for easing sanctions.
