He has also advocated for a more aggressive approach to Venezuela as Trump’s interim national security adviser.
His stance contrasted with the more accommodating strategy towards Russia advocated by Trump’s long-time friend and special envoy Steve Witkoff.
White House spokeswoman Anna Kelly pushed back on the characterisation of Rubio’s role.
“President Trump always leads on foreign policy, and his agenda is executed by national security officials like Secretary Rubio and Special Envoy Witkoff, who are one, unified team behind the President’s America First vision,” she said.
There’s no indication that Witkoff, one of Trump’s most trusted confidantes, has lost his standing on the Russia file with the President, or his influence more broadly.
He was shuttling around the Middle East this week overseeing a fragile ceasefire in Gaza that he helped Trump negotiate.
However, some of the people said Witkoff’s discussions with Putin and other top officials in the run-up to an earlier summit, in Alaska, led to confusion and the perception that Moscow was prepared to make concessions it had no intention of carrying out.
Kelly, the White House spokeswoman, denied that was the case.
She said Witkoff is “clear with everyone” and he and Trump are working towards peace with “a complete and accurate understanding of all the factors at play”.
That August summit was tense as Putin insisted on negotiating about Ukrainian territory, frustrating Trump and leading him to nearly walk out of the room, the people said. This time, Rubio led the preparatory groundwork.
The State Department earlier characterised Rubio’s call with Lavrov as productive. Asked about Rubio’s role this time around, State Department spokesman Tommy Pigott said the “entire team is fully unified around President Trump’s leadership”.
People suggesting otherwise are wrong, he said. “Harmful actors are pushing selfish agendas through baseless lies,” he said.
“President Trump and his team have already accomplished more in the pursuit of peace than anyone thought possible, and as the President said, that is in large part because of the unprecedented success of Special Envoy Witkoff.”
Despite the difficult first summit, Trump earlier this month agreed to meet Putin again after a lengthy phone call.
US officials had hoped to capitalise on diplomatic momentum in the wake of Trump winning praise for helping secure a long-sought truce that ended two years of hostilities between Israel and Hamas.
Russia sent the US a plan outlining its terms for peace with Ukraine that rehashed all of its well-known positions, including demands Ukraine give up more territory, some of the people said.
“Last time, it took the meeting in Alaska for the US to realise that there’s no flexibility on the Russian side,” said Liana Fix, a senior fellow at the Council on Foreign Relations.
“This time, this realisation took place before the meeting, which is a good step.”
On the Russian side, there was also confusion.
Russian officials left the Putin-Trump call believing the US President had agreed to Russia’s demand that Kyiv give up the remainder of the strategic Donbas region in return for only modest territorial concessions by Moscow, according to a person familiar with the Kremlin’s thinking.
A day later, after meeting Ukrainian President Volodymyr Zelenskyy, Trump reiterated that he wanted a ceasefire along the current battle lines, an idea that Moscow had rejected ahead of the Alaska summit, this person said.
Lavrov highlighted this disagreement in his call with Rubio last Tuesday, the person said.
By that point, the summit preparations were falling apart.
While Rubio sat down alongside Witkoff in Saudi Arabia when the Administration first pursued direct talks with Russia in February, his more direct involvement this time around has been a relief for many European officials who said they were worried that the US - under Witkoff’s guidance - could shift too far towards Russia’s position, piling pressure on Ukraine to accept Moscow’s demands.
During Trump’s meeting with Zelenskyy last week, for instance, Witkoff had again pressed the wartime leader to agree to Putin’s demands to cede the Donbas to Russia, the people familiar said.
Last Thursday, Trump’s Administration slapped sanctions on Russia’s biggest oil producers, blacklisting state-run oil giant Rosneft PJSC and Lukoil PJSC.
“Every time I speak with Vladimir, I have good conversations, and then they just don’t go anywhere,” Trump told reporters in the Oval Office after the sanctions announcement, adding the White House may arrange a future meeting.
Rubio nevertheless left open the possibility of further engagement with Moscow, including future meetings.
Speaking to reporters at Joint Base Andrews outside Washington before a trip to Israel and Asia, Rubio said “we’re always going to be interested in engaging if there’s an opportunity to achieve peace”.
“I think the President has said repeatedly, for a number of months now, that at some point he will have to do something if we don’t make progress on the peace deal,” Rubio said. “Today was the day he decided to do something.”
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