Woodstock (United Kingdom) (AFP) - UK Prime Minister Keir Starmer on Thursday pledged to strengthen ties with European allies on security and illegal migration, insisting “Britain is back” as he seeks to rebuild bridges after Brexit.

Labour leader Starmer, elected premier two weeks ago, said the UK would be “resetting our approach” as he started work to improve relations hit by the country’s tortuous departure from the European Union under his Conservative predecessors.

“We are going to deepen our cooperation on defence and security and on illegal migration,” he told more than 45 leaders as he opened the European Political Community (EPC) meeting at Blenheim Palace, the birthplace of Winston Churchill.

Europe is grappling with challenges ranging from supporting Kyiv after Russia’s full-scale invasion to breaking up people-smuggling gangs contributing to record levels of irregular migration.

In the background hangs the increasing possibility of Donald Trump regaining the White House in November, with fears over his commitment to the Western military alliance NATO.

Trump’s newly elected running mate J.D. Vance is an outspoken critic of military aid to Ukraine and has pushed for negotiations with Russia to end the two-year-plus war.

“It’s very important to be here, for Ukraine, especially this tough period, for us during the war,” Ukrainian President Volodymyr Zelensky said at Blenheim Palace, near Oxford, southern England.

“For us it’s very important to maintain unity in Europe because always this unity leads to strong decisions,” added Zelensky.

While at the summit, the Ukrainian leader signed long-term security cooperation agreements with the Czech Republic and Slovenia.

NATO Secretary General Jens Stoltenberg, attending an EPC summit for the first time, insisted aiding Ukraine must remain a “joint effort” by Europe and the United States.

- ‘No silver bullet’ -

In a departure from the often fractious relations that characterised the run-up to Brexit, Starmer, who led Labour to a landslide election win over the Tories on July 4, told European counterparts that his government would be “a friend and a partner ready to work with you”.

He called irregular migration a “crisis” affecting every country attending. More than 380,000 undocumented migrants crossed the EU’s borders last year, and tens of thousands made their way to Britain.

The issue embarrassed Tory administrations under Boris Johnson, Liz Truss and Rishi Sunak, who had promised tough action to “take back control” of Britain’s borders after Brexit.

Starmer called for a sharing of resources, intelligence and tactics to “shut down the smuggling routes and smash the gangs” behind migrant Channel crossings from northern France in small boats.

He agreed initiatives with Slovenia and Slovakia to tackle organised crime, and pledged £84 million ($108 million) to help address poverty driving migrants to Europe.

Cooperation was “the most efficient” way to tackle the problem, French President Emmanuel Macron said, the morning after one migrant died and 71 others were rescued off the French coast.

But he warned there was no “silver bullet” to solve the issue.

- ‘Game changer’ -

Starmer had one-on-one conversations with several European leaders, including Macron, as he fleshed out what he wants Britain’s renewed relationship with the EU to look like.

The former human rights lawyer and chief state prosecutor supported Britain remaining in the EU during the 2016 Brexit referendum and was once Labour’s Brexit spokesman.

He has ruled out rejoining the European single market, customs union or freedom of movement, however – to avoid reopening what remains a thorny issue among British politicians and public alike.

But he does want to negotiate a new security pact with the bloc and a veterinary agreement to ease border checks on agricultural foods, as well as an improved trading deal.

The EU has said it is open to discussing improvements, but Macron warned there could be no “cherry-picking” by London.

Starmer was quick out of the blocks to congratulate Ursula von der Leyen on securing another term as European Commission president. He eagerly anticipated “working closely” with the EU chief, he said.

Irish premier Simon Harris described Labour’s reset with Europe as a “game changer” while European Council chief Charles Michel said he hoped that a “new chapter” would be opened with the UK.

The choice of Blenheim Palace and its associations with Churchill added further symbolism to proceedings. The Treaty of London, which signed into existence the Council of Europe in 1949, was on display.