A UK foreign office minister has suggested that the Bank of England grant access to £1.2bn in Venezuelan gold reserves to the self-proclaimed interim leader Juan Guaidó rather than Nicolás Maduro.

In a statement to British MPs, Sir Alan Duncan said the decision was a matter for the Bank and its governor, Mark Carney, and not the government. But he added: “It is they who have to make a decision on this, but no doubt when they do so they will take into account there are now a large number of countries across the world questioning the legitimacy of Nicolás Maduro and recognising that of Juan Guaidó.”

Guaidó has already written to Theresa May asking for the funds to be sent to him.

Profile Who is Juan Guaidó? Show The opposition leader Juan Guaidó was almost unknown both inside and outside Venezuela until the start of this year. Guaidó was made chairman of the national assembly in January because it was the turn of his party, Voluntad Popular (People’s Will). At 35, he was a junior member of his party but its leaders were either under house arrest, in hiding or in exile. He declared himself "interim president" that month, resting his claim on a clause in the constitution that allows the legislature to take power temporarily and call new elections if it deems the president to be failing to fulfil basic duties or to have vacated the post. Guaidó's relative obscurity initially proved an advantage in a country where the opposition has generally failed to distinguish itself, losing its nerve at critical moments, succumbing to infighting, and getting involved in a failed coup against Hugo Chávez in 2002. He inspired a huge wave of protests inside Venezuela with a message of peaceful change, and won widespread international support. Countries from Europe to the US and regional powers recognised him as Venezuela's legitimate president, handing him control of bank accounts and Venezuelan assets along with the formal recognition. As months dragged on however, Guaidó's hope of winning a wave of military defections that would end the rule of Nicolás Maduro seemed to fade, leaving his movement in an uneasy limbo - self-declared president but with no power. He raised concerns inside Venezuela and internationally when he appeared to hint at the possibility of military intervention after a failed attempt to bring humanitarian aid into the country in February. Questions have also been raised about the bedfellows Guaidó has chosen in what he calls his bid to rescue Venezuela. His main international backer is Donald Trump.

Another key regional supporter is Brazil’s far-right firebrand president, Jair Bolsonaro, known for his hostility to human rights and his fondness for dictatorship. Despite these characteristics, Guaidó has praised what he called Bolsonaro’s “commitment to and for democracy [and] human rights”. Photograph: Luis Robayo/AFP

The former chair of the foreign affairs select committee Crispin Blunt said the current Venezuelan central bank president was not legitimate, since he had not been appointed by the country’s national assembly. Blunt has sent letters to the foreign secretary, Jeremy Hunt, and to the chancellor, Philip Hammond, urging a decision.

Duncan said Hunt would be discussing the next steps in the European Union’s efforts to support Guaidó in Bucharest on Thursday. Key EU states including France, Germany, Spain and the UK on Saturday urged Maduro to call free and fair elections within eight days or else see Guaidó recognised as interim president by the international community. The EU stance was backed by the SNP and the Liberal Democrats in the Commons.

For all the international criticism of the Maduro government, there are concerns that Guaidó’s main regional backers are Donald Trump and Jair Bolsonaro, Brazil’s far-right president.

Emily Thornberry, the shadow foreign secretary, said democracy had ceased to function in any meaningful way in Venezuela and that its people needed a government that respected the rule of law and upheld human rights and democracy, but she cautioned against a rush to oust Maduro.

Venezuela’s president, Nicolás Maduro, touches a gold bar a during a meeting with ministers last March. Photograph: Marco Bello/Reuters

“Judging by its record in recent years, the Maduro government fits none of those descriptions, but I would also believe that it is a mistake in situations like this simply to think that changing the leader will automatically solve every problem, let alone the kind of US-led intervention being threatened by Donald Trump and [the US national security adviser] John Bolton.”

She said Britain’s chief priority should ultimately be to allow the Venezuelan people to decide the way forward through free and fair elections.

Thornberry’s remarks appeared to distance Labour from the eight-day deadline set by the EU. Maduro has rejected the deadline, insisting that his government will not fall to a coup.

The Liberal Democrat foreign affairs spokeswoman, Jo Swinson, said an interventionist approach was justified given the humanitarian crisis and the rigged elections conducted by Maduro. Duncan repeatedly pointed out that Maduro’s neighbouring countries had referred Venezuela to the international criminal court.

But the former Conservative cabinet minister Kenneth Clarke advised against opposing further economic sanctions and confessed his trepidation about what the US was seeking to achieve. He recommended economic sanctions to force the military to withdraw its support for Maduro.

Duncan said he recognised the need for caution. “The narrative of US interference in Latin America can stir up counterproductive voices when what we want to do is solve the problem, rather than relive some of the difficulties of a few decades ago,” he said.