By Olena Harmash and Sergiy Karazy
KYIV (Reuters) -Prime Minister Keir Starmer pledged on Thursday to work with Ukraine and allies to offer Kyiv robust security guarantees if a ceasefire is negotiated with Russia, offering more support to President Volodymyr Zelenskiy with a 100-year partnership deal.
In his first trip to Ukraine since becoming prime minister in July last year, Starmer was keen to underline Britain's support for the nation just days before Donald Trump returns to power in the United States.
In talks punctuated by the sound of a loud explosion from Ukraine's air defences shooting down a Russian drone above the presidential palace, Zelenskiy said he had spoken to Starmer about Kyiv's desire for Western peacekeeping troops to be deployed in Ukraine in the event of peace.
Starmer said Britain would look at "the practical ways to get a just and lasting peace ... that guarantees your security, your independence and your right to choose your own future", but declined to go into any details of which measures he supported.
"We will work with you and all of our allies on steps that would be robust enough to guarantee Ukraine's security," Starmer told a press conference alongside Zelenskiy. "Those conversations will continue for many months ahead."
Pressed in an interview with Sky News on whether Britain would contribute troops to any peacekeeping force, Starmer said: "I've been discussing this with a number of allies, including, of course, (French) President Macron, including President Zelenskiy here today, and we will play our full part."
Starmer's visit comes two days after German Defence Minister Boris Pistorius also travelled to the country, with European leaders weighing what security guarantees they can provide as part of any peace agreement that may be pushed by Trump.
Trump's return to the White House has drawn concerns that a bid to end Moscow's war could force Ukraine to cede large parts of the country to Russia for the foreseeable future.
Zelenskiy said he had also spoken to France, Poland and the Baltics about a possible peacekeeping deployment to deter Russia from mounting any future attack after a ceasefire and expressed frustration at nations' opposition to Ukraine's bid to become a member of the U.S.-led military NATO alliance.
But Starmer urged Ukraine and the West should not lose focus of the most pressing need to "ensure that Ukraine is in the strongest possible position" in 2025 to fight Russia.
"We're a long way into this conflict. We mustn't let up."
PARTNERSHIP DEAL
As the war against Russia approaches its three-year mark, Ukraine is on the backfoot on the front lines. Ukrainian forces are suffering from manpower shortages and losing ground in the eastern Donetsk region as Russia's troops continue their advance.
Since Russia's invasion in 2022, Britain has been a vocal supporter of Ukraine, with Starmer's predecessors visiting Kyiv in the early days of their tenure.
It took a little longer for Starmer to make the trip, but he comes armed with a 100-year partnership with Kyiv to deepen security and cultural ties.
The treaty and political declaration aims to boost military cooperation to strengthen security in the Baltic Sea, Black Sea and Sea of Azov and deter Russian aggression.
The treaty will also cover areas such as energy, critical minerals and green steel production, Starmer's office said.
"Putin's ambition to wrench Ukraine away from its closest partners has been a monumental strategic failure," Starmer said in a statement. "Instead, we are closer than ever, and this partnership will take that friendship to the next level."
Britain has provided 12.8 billion pounds ($16 billion) in support to Ukraine since in 2022, a sum dwarfed by Washington's $63.5 billion in security assistance, underscoring the importance of Trump's actions over Ukraine.
The partnership announced on Thursday, which provides 40 million pounds for Ukraine's economic recovery, includes additional support around grain verification and trade with Ukraine's thriving technology sector that has produced battle-ready equipment.
($1 = 0.8185 pounds)