The head of Britain's main opposition party promised on Thursday to put people smuggling on a par with terrorism and forge closer intelligence ties with Europe if elected to government.
Keir Starmer's Labour is well ahead of the ruling Conservative party in opinion polls, putting it on course for a return to office for the first time since 2010.
Starmer, 61, has faced growing calls to put more flesh on the bones of his party's policies for power, as he looks to supplant Rishi Sunak as prime minister in Downing Street.
On Thursday, he travelled to The Hague to meet officials from Europol -- one of several overseas visits designed to portray the former state prosecutor as Britain's leader-in-waiting.
He heads to France next week to meet President Emmanuel Macron and is also said to be heading to Canada to meeting Prime Minister Justin Trudeau.
Starmer said deepening intelligence ties with Europe was key to tackling organised immigration crime and the record number of "small boats" crossings that have plagued the government.
"The government's failure to tackle the criminal smuggling gangs orchestrating boat crossings is now so profound that I believe it needs to be considered on a par with the other three big security threats we face -- climate change, hostile foreign powers and terrorism," he added.
Labour would work to reach a new deal to share real-time intelligence with the European Union, similar to the Schengen Information System II database of terror suspects and immigration offenders, he said.
The UK previously had automatic access to the system until it left the EU three years ago.
Starmer also promised to send more UK police officers to Europe, with a dedicated "cross-border police force" to tackle criminal gangs behind the dangerous Channel crossings.
He also indicated he could do a deal with Brussels to take a quota of asylum seekers from the EU in exchange for the UK being able to return migrants who cross the Channel.
Plans first introduced under Sunak's predecessor Boris Johnson to send failed asylum seekers to Rwanda caused outrage and are mired in legal action.
Starmer's preparations for government include a recent reshuffle of his top team, an outline of his environmental policies, and a series of pledges to the party's trade union backers.
Deputy leader Angela Rayner on Tuesday promised an overhaul of workers' rights within the first 100 days of a Labour government, and an end to the legal requirement of minimum service during strikes.