A girl was born on a rescue ship in the Mediterranean after her mother was one of more than 4,500 migrants picked up in a single day.

The numbers reaching southern Europe by sea has soared by more than 60 per cent in the first six months of this year, compared to the same time last year.

The Italian coastguard yesterday revealed that improving weather conditions had led to thousands being rescued between North Africa and Italy on Tuesday alone.

A Cameroonian woman gave birth on naval vessel Bettica after she was saved from a dinghy in distress.

The newborn was named Manuela after the midwife who delivered her on the ship.

More than 1,100 people were saved by a single Italian coastguard patrol vessel, which took on board the passengers of a stricken wooden boat and five dinghies.

The wooden craft had 435 migrants aboard, including 124 women and 18 children, according to a spokesman for the coastguard.

Four Italian naval vessels saved more than 900 others, while boats belonging to charities and aid groups, the EU border patrol agency Frontex and the EU’s anti-people smuggling mission rescued the remaining migrants.

An estimated 227,316 migrants have arrived in Europe from Africa and the Middle East over the course of the first six months of 2016.

This is an increase of around 85,000 – or 60 per cent – on the 141,969 who made the trip during the same period last year.

More than 158,000 of the migrants had crossed to Greece, however, that route has become much less popular since March, when the EU signed a £5billion deal with Turkey to return all new arrivals.

In the first six months of 2015, 1,838 migrants died attempting the journey to Europe by boat, according to the figures from the International Organisation for Migration (IOM). This year, the death toll so far is 2,920.

The EU’s border agency boss last month admitted the search and rescue operation in the Mediterranean has encouraged thousands to attempt to get to Europe.

Frontex director Klaus Roesler said the naval mission that picks up migrants off the North African coast and ferries them to Italy had ‘triggered departures’.

He forecast that 10,000 would make the crossing every week for the rest of this year – a total of around 300,000.

Critics have claimed the operation has ‘descended into a ferry service’ that has turned the route into a ‘magnet for migrants’. Smugglers are setting off from the North African coast in boats with only enough fuel to get them into international waters.

They then telephone rescuers asking for help knowing they will be picked up by EU ships that take them the rest of the journey to Italy.

A House of Lords report in May warned that the search-and-rescue operation acts as a ‘magnet to migrants and eases the task of smugglers’ but ‘does not ... in any meaningful way deter the flow of migrants, disrupt the smugglers’ networks, or impede the business of people-smuggling on the central Mediterranean route’.

And last month the Libyan coastguard claimed the EU had been enticing migrants to their deaths off its shores.