Fewer people are making the journey across the Mediterranean to Europe, but the proportion of those losing their lives while trying has risen sharply, the UN refugee agency has said in its latest report.

The UNHCR said 1,095 people died on the central Mediterranean route, mainly from Libya to Italy, between January and July this year, amounting to one death for every 18 arrivals. This compares with 2,276 last year, or one death for every 42 arrivals.

In June, the proportion hit one death for every seven arrivals, the agency said, adding that there had been 10 incidents so far this year in which 50 or more people died, most of them after leaving Libya and seven of them since June.

“The reason the traffic has become more deadly is that the traffickers are taking more risk, because there is more surveillance exercised by the Libyan coastguards,” said Vincent Cochetel, the UNHCR’s special envoy for the central Mediterranean.

More than 300 people had also died so far in 2018 along the sea route from North Africa to Spain, the UNHCR said – a 50% increase on 2017, when 200 deaths were recorded for the whole year. In April, when more than 1,200 reached Spain by sea, the death rate was one in 14.

“With the number of people arriving in Europe falling, this is no longer a test of whether Europe can manage the numbers, but whether Europe can muster the humanity to save lives,” UNHCR’s Europe bureau director, Pascale Moreau, said.

Migration into Europe is down sharply from its 2015-16 peak, but the bloc remains divided over how to handle new arrivals. The interests of “frontline” southern states, such as Italy and Greece, are diametrically opposed to those of northern “destination” states, and some hardline, populist leaders are refusing to take any refugees at all.

Italy’s far-right interior minister, Matteo Salvini, has said his country will “no longer be Europe’s refugee camp”, and sparked a series of diplomatic rows by refusing to allow migrant rescue ships to dock in Italian ports unless other EU states agreed to take in those onboard.

Salvini and the equally hardline Hungarian prime minister, Viktor Orbán, said after meeting in Milan last week they were “walking down the same path” in opposing what they called the “pro-migration policies” of the European commission and France’s president, Emmanuel Macron.

The UN migration agency, IOM, has demanded a “predictable, regional approach” for the rescue and disembarkation of people recovered in the Mediterranean, and the UNHCR is calling for Europe to provide increased access to safe, legal pathways for refugees by boosting resettlement places and cutting obstacles to family reunification.

Cochetel said Europe needed to come together and “take the lead”, avoiding anti-migrant rhetoric and understanding that numbers were sharply down and migrant flows manageable at current levels.

The UNHCR also outlined the dangers refugees face travelling to or within Europe by land, saying 78 deaths had been recorded so far this year along land routes in Europe or at Europe’s borders, compared with 45 in the same period last year.