Illegal immigration to Europe via the Mediterranean has cracked 70,000, as a surge in migrants to Spain partly offsets the effect of tighter border controls in Greece and especially Italy.

While the number is significantly down on recent years — particularly the peak year of 2015, when hundreds of thousands of migrants surged into Europe largely via Greece and the ‘Eastern Mediterranean Route’ at the invitation of Germany’s Angela Merkel — it is still far from insignificant, with the numbers being not far off the total manpower of the British Army.

Moreover, the official UN Migration Agency/International Organization for Migration figures may significantly underestimate the true scale of the influx, as they do not account for migrants whose arrival goes undetected.

The Dutch government has previously suggested that some two-thirds of the migrant arriving in the Netherlands have not previously been registered in another EU member-state — although the great majority arrive from one — and hinted this may be deliberate.

EU member-states cannot deport illegal migrants to the last EU country they were in, and must instead determine the first EU country they arrived in or keep them. Naturally, this serves to disincentivise border countries such as Greece, Italy, and Spain from registered migrants at all.

The figures show arrivals to Italy, which had become the main entry point to Europe for illegal migrants after Brussels began paying Turkey billions of euros to stop the influx to Greece, have collapsed to their lowest level since 2014.

A large share of the credit for this is likely due to the country’s new populist coalition government, and in particular Deputy Prime Minister and Minister of the Interior Matteo Salvini, who has acted strongly against NGO ‘rescue’ ships ferrying migrants across the Mediterranean after collecting them from smuggler boats a few miles off the North African coast.

In Spain, however, the picture is reversed, with illegal migration increasing significantly following the instalment of a new Socialist Party government — partly through sea ‘rescues’ or migrant boats simply driving straight across the sea and disgorging their human cargo onto packed tourist beaches, and partly through violent, organised attacks on Spain’s land borders with Morocco, around the exclaves of Ceuta and Melilla.

Follow Jack Montgomery on Twitter: @JackBMontgomery