A second Royal Navy warship has been deployed to the Mediterranean to aid the EU's fight against people smugglers.
The Ministry of Defence (MoD) announced frigate HMS Richmond arrived to join patrols off the coast of Libya aimed at stopping human traffickers who risk the lives of refugees by taking them on the perilous journey to Europe by boat.
Defence Secretary Michael Fallon vowed to "hit the traffickers hard".
HMS Enterprise is already stationed in the region to gather intelligence but was called into action last month to save nearly 400 migrants after Italian authorities were overwhelmed.
HMS Richmond's commanding officer will have powers to board and seize boats suspected to be used in people smuggling following the adoption of a United Nations Security Council resolution, the MoD said.
Mr Fallon added: "These new powers are an important step forward. We will now be able to board the boats and detain the smugglers.
"Sending HMS Richmond to join HMS Enterprise in the Mediterranean shows Britain's determination to tackle this trade in human misery at source."
HMS Enterprise replaced HMS Bulwark, which saved 3,000 lives in the Mediterranean, in July as part of a wider EU mission to detect and disrupt people-smuggling gangs.
More than 600,000 migrants have arrived in the EU by boat over the course of 2015 - around 475,000 landing in Greece and 137,000 in Italy - according to figures from the International Organisation for Migration.
The body estimated more than 2,000 people have died trying to make the crossing so far this year.
The announcement also comes after four boats carrying migrants landed at the RAF air base at Akrotiri in Cyprus on Wednesday.