Jeremy Corbyn has been criticised by his own MPs for failing to directly condemn the Venezuelan regime led by president Nicolas Maduro as the South American country descends further into chaos.
The Labour leader denounced the violence inflicted by "all sides" during the crisis despite pressure to personally criticise Mr Maduro, who has been accused of behaving like the "dictator of an evil regime" by Foreign Secretary Boris Johnson.
Veteran Labour MP Frank Field suggested the Labour leader's comments do not befit a politician who aspires to be British prime minister.
And former minister John Spellar called for Mr Corbyn to unequivocally recognise the failure of Mr Maduro's government.
Mr Corbyn has previously supported the left-wing governments of Venezuela but, while on holiday in Croatia, remained silent as Mr Maduro cracked down on his enemies following a widely disputed vote which gave his ruling socialist party near unlimited powers.
Speaking in Crawley, West Sussex, where he was attending a meeting of Labour Party members, Mr Corbyn said: "I'm very sad at the lives that have been lost in Venezuela. The people who have died, either those on the streets or security forces that have been attacked by people on the street - all of those lives are terrible for the loss of them.
"There has to be a dialogue and a process that respects the independence of the judiciary and respects the human rights of all."
Asked whether he condemned Mr Maduro's actions, Mr Corbyn said: "What I condemn is the violence that's been done by any side, by all sides, in all this. Violence is not going to solve the issue.
"The issues in Venezuela are partly structural because not enough has been done to diversify the economy away from oil - that has to be a priority for the future.
"But we also have to recognise that there have been effective and serious attempts at reducing poverty in Venezuela, improving literacy and improving the lives of many of the poorest people."
Pressed on whether he regretted supporting Mr Maduro when he was elected, he said: "I gave the support of many people around the world for the principle of a government that was dedicated towards reducing inequality and improving the life chances of the poorest people."
He said he backed French president Emmanuel Macron's call for a dialogue, and said it "should be regionally based to improve the situation there".
"There has to be respect for the constitution and respect for the independence of the judiciary."
Reacting to Mr Corbyn's comments, Mr Field told the Press Association: "Voters in this country expect future prime ministers to be robust in defending the independence of the judiciary, respect for human rights and a parliamentary process.
"They've had their dialogue on this a long time ago."
Fellow Labour MP Mr Spellar suggested Mr Corbyn was too ambiguous and called on his leader to "unequivocally" recognise the failure of the Maduro regime.
Mr Spellar, who is a member of a new all party parliamentary group (APPG) on Venezuela, told PA: "Venezuela has the world's largest oil reserves yet its incompetent regime has created a national catastrophe of rampant hyperinflation and a chronic shortage of basic household necessities, even toilet paper.
"We should be clearly on the side of Venezuelan freedom and should be calling for respect for the clear mandate of the freely elected national assembly and the freeing of all political prisoners.
"That should be the position of the Labour Party."
He said Mr Corbyn should "come down clearly, recognise the failure of the regime, the political crisis that that has created and to stand firmly with the people of Venezuela and the proper constitutional bodies," adding that the leader's statement "doesn't do that".
"He's just got back off holiday, I think he needs to reconsider and come out with an unequivocal statement on the lines that I've described, recognising the crisis and standing with the people of Venezuela," Mr Spellar said.
As a backbencher, Mr Corbyn hailed former Venezuelan leader Hugo Chavez as an "inspiration to all of us fighting back against austerity and neo-liberal economics in Europe".
He supported parliamentary motions linked to the country, including one which congratulated Mr Maduro on his election as president, and called for closer ties with Caracas.
Liberal Democrat leader Sir Vince Cable said: "Labour have again failed to condemn President Maduro as he slides his country closer to dictatorship. It remains a source of fascination that the far-left see what is happening in Venezuela as some kind of role model for British politics.
"The whole idea that Chavez and his successor could serve as a dry run for government in the UK is absolutely horrifying.
"Venezuela is facing a complete economic collapse with hyperinflation and chronic shortages of basic necessities. This is essentially a rich country slipping into deep poverty, all the while eroding democratic institutions and the rule of law.
"The leadership of the Labour Party must make it abundantly clear that they have ended their infatuation with the Venezuelan regime."
Responding for the Tories, International Development Secretary Priti Patel said: "Incredibly, Jeremy Corbyn has flat out refused to condemn the brutal regime championed by his socialist ally and friend, President Maduro.
"The sheer brutality of the government in Venezuela is appalling.
"Poverty and malnutrition are rife, people are queuing up for rice and milk, hospitals have run out of medical supplies and parents are so desperate, they are handing their children over to the state.
"Despite the destitution and the depravity of Maduro's government, Corbyn fails to criticise Maduro.
"What will it take for Corbyn to finally urge Maduro to stop the violence, the human rights abuses, the poverty and the killings?"
Labour MP Angela Smith, another member of the Venezuela APPG, said: "It is right that Jeremy should condemn violence on all sides but he needs to go further.
"The vitally important question is whether or not democracy can survive in Venezuela, given the recent actions of Maduro's government, and Corbyn needs to make it clear that he is on the side of democracy."