Nearly 6,000 mostly African migrants have landed at southern Italian sports since Tuesday but Prime Minister Matteo Renzi said the overall trend this year was broadly in line with the 2015 pattern.
"We are not facing an invasion," the premier told a press conference after the figures were released by the International Organisation for Migration in Geneva.
Fears are running high in Italy that it could pay the price of EU moves to close routes through the Greek Islands and the Balkans.
Italian officials are also wary of the possibility of neighbouring EU countries closing their borders, as France did temporarily last year and Austria is threatening to do now.
Austria has begun preparing for a possible reintroduction of border controls at the Brenner pass in the Alps, prompting protests from Italy and the European Commission.
Renzi warned Friday of repercussions if Vienna did close the border.
"If the rules are broken we cannot act as if nothing has happened," he said.
Italy's interior ministry this week asked local authorities to find 15,000 extra beds to house asylum-seekers in anticipation of a possible increase in the numbers of people requiring accommodation.
"There is a problem that concerns our country but there is not an invasion underway," Renzi said.
"We have taken certain initiatives but we are not facing an invasion. It is a big problem but we have clear ideas about how to deal with it."
Few Syrians in Libya
Renzi said the EU was working on deals with African countries to stem the flow of migrants leaving for Europe and to prevent those who do from being allowed to pass through transit countries.
The IOM said that of the 6,021 migrants who have reached Europe by sea since Tuesday, only 174 had landed in Greece, with the balance coming ashore in Italy.
Late Friday, Austria's interior minister Johanna Mikl-Leitner said Vienna was anticipating a "significantly increased migration flow via Italy".
Mikl-Leitner sent a letter to EU Migration Commissioner Dimitris Avramopoulos stressing that "adequate preparatory measures" were needed, according to the Austria Press Agency.
"It must also be taken into account that migration routes can also be used by members of terrorist groups, as the attacks in Paris and Brussels showed," the letter added.
IOM spokesman Joel Millman stressed there was no evidence yet to suggest the Italy arrivals were linked to an EU-Turkey deal aimed at stemming the influx of people to the Greek islands.
German Chancellor Angela Merkel and top EU officials will visit an area near the Turkish-Syrian border next week to follow up on the EU Turkey migrant deal, officials said Friday.
The European Union sealed the deal with Ankara last month under which Turkey takes back all "irregular migrants" who arrive in the Greek islands in exchange for billions of euros in aid for refugees and political concessions.
'Increase in numbers'
Migrants who spoke to IOM staff in Italy all said they had crossed from Libya, most of them on rubber dinghies loaded with around 130 people.
"Many of them were from sub-Saharan Africa, and we have noticed an increase in numbers from the Horn of Africa, particularly Eritreans," Federico Soda, head of the IOM's Rome office, said in a statement.
"There have been very few Syrians leaving from Libya in recent months," Soda said.
Italian officials believe that any Syrians seeking to get into Europe via Libya are more likely to come via Albania, from where it is just a short crossing to the southeastern coast of Italy.
So far this year, more than 23,000 migrants have landed in Italy, compared to nearly 153,500 who have landed in Greece, the IOM said.
Italy's interior ministry put arrivals in Italy at 23,739 since the start of the year as of Thursday morning, compared to 19,589 by April 14 last year.
That represents a rise of 21 percent, but officials urge caution in interpreting figures as the pattern of the last two years has been for migrants to arrive in bursts often dictated by weather and sea conditions.
There are an estimated one million non-Libyan nationals living and working in Libya.
This has led to speculation that a deterioration in the security situation in the country could result in many of them seeking to reach Italy.