ATHENS — The Greek government's tough stance on migration doesn't go far enough for conservatives in the ruling New Democracy party like ex-Prime Minister Antonis Samaras, who is goading his successor to crack down on what he calls an "invasion by illegals" who are "colonizing" Greece.

Kyriakos Mitsotakis, who ousted the left-wing Syriza in July's election partly on a promise to crack down on abuse of the asylum system, is trying to draw a balance between tougher rules and conditions in camps for asylum seekers, and not imitating far-right, xenophobic parties like Golden Dawn and Greek Solution.

But with flows of migrants at their highest since the EU-Turkey agreement of 2016, which was designed to stem arrivals to Europe, and more than 67,000 people arriving in Greece so far this year, the center-right New Democracy is under pressure from Samaras and others for a much more strident approach.

It is also feeling the heat of public opinion: Polls suggest migration tops the list of voters' concerns and that the new government is under-performing on the issue. Ordinary Greeks' tolerance toward refugee camps, especially in the islands where they are currently located, seems to have been exhausted, while any attempt to relocate them meets stiff opposition and protest from angry communities near the new sites.

Peppering up an otherwise dull party congress in early December, Samaras argued in an aggressive speech that “illegal intruders,” mainly from countries where there is no war or other conditions that would justify granting them asylum, are staging an “informal illegal colonization” of the country.

Before coming to power, New Democracy accused Alexis Tsipras' left-wing government of being too soft and ideological on migration — only to see the situation deteriorate quickly after Mitsotakis took office.

In fact, even though New Democracy government figures dispute this, the U.N. High Commissioner for Refugees Filippo Grandi says U.N. data shows the majority of these arrivals do originate from countries whose situation could make them eligible for asylum, such as Afghanistan and Syria.

Samaras, whose backing helped put Mitsotakis in office but who then failed to get the new government's nomination for the post of European commissioner, called for a return to the policies of his 2012-2014 administration, which he summarized as “closed camps and back to their countries."

"This policy was implemented and this policy worked. This is the policy the new government has promised,” the 68-year-old former leader said, accusing Brussels for good measure of behaving like “an irresponsible observer commenting from afar.”

Before coming to power, New Democracy accused Alexis Tsipras' left-wing government of being too soft and ideological on migration — only to see the situation deteriorate quickly after Mitsotakis took office.

The government has already pushed through legislation making it easier to deport failed asylum seekers and has promised to shut down notoriously overcrowded reception centers on the islands and replace them with closed camps and restricted centers on the mainland — all to the horror of refugee aid organizations.

Manos Logothetis, the government's special secretary for the reception of migrants and refugees, said the change in approach meant they would be treated as "guests" of the country, "not customers."

All of the island centers would be replaced by closed camps by next June and the inmates would only be able to leave the camps according to a strict timetable, “for their own protection, but also so that the system can operate better," he told POLITICO.

Although Samaras' intervention at the party congress sounded like a reproach to Mitsotakis — possibly because he was overlooked for the Commission job and his candidacy for the Greek presidency is not being favored by the government — one close associate of the former premier said the terminology he used was "common in public discourse of New Democracy members, including Mr. Mitsotakis himself, before 2015.”

But Samaras also has the ear of other prominent party members who joined New Democracy in recent years from the small nationalist party Laos, such as the current agriculture and development ministers.

One New Democracy MP proposed "breaking the taboo" and sending asylum seekers to remote, uninhabited islands.

“He expressed what the whole of Greek society is discussing,” said Agriculture Minister Makis Voridis.

“I agree with every word of Mr. Samaras' speech,” said Development Minister Adonis Georgiadis, who added that although Mitsotakis used different rhetoric, he had basically copy-pasted Samaras' policy ideas.

Nick Malkoutzis, the editor and co-founder of the website MacroPolis, said a sizeable chunk of the ruling party appeared to favor a hard line on refugees — partly in the belief that this would prevent leaking votes to parties further to the right, but partly reflecting the belief among some New Democracy cadres "that a tough stance on migration should be a cornerstone of ND's politics."

That explains why, when a group of anti-immigrant protesters organized a barbecue with alcoholic drinks last month outside a camp containing many Muslim asylum seekers, one New Democracy MP defended the action and said Greeks shouldn't change their culture to accommodate the newcomers. Another MP from the party proposed "breaking the taboo" and sending asylum seekers to remote, uninhabited islands.

Meanwhile, "others in the center-right party appear to have a more nuanced position, which creates an uneasy political and ideological balance,” said Malkoutzis. He added that the government's tough stance on refugees "undermines their calls on locals for greater assistance" in dealing with the influx.

“There is a danger that we see in Greece a repeat of what has unfolded in other European countries where refugees and migrants have been stigmatized, which is that they become physical as well as political targets and voters become increasingly attracted to extremist views,” said the analyst.

That risk has already been highlighted by rights groups, NGOs and the UNHCR's Grandi, who said on a recent visit to Greece that “patience and hospitality are now less visible than before.”

Inside New Democracy, one of the MPs recommending a more moderate approach is Mitsotakis' own sister Dora Bakoyannis, a fellow New Democracy MP and former foreign minister, who tweeted that some "young MPs" with strident opinions "didn’t understand what they were talking about” and that she did not believe anyone in the party was in favor of an inhumane approach to the migration crisis.