Hugo Chavez, Venezuela's president for nearly 14 years, has died after battling with cancer.
The man who led a leftist revolution in the South American country had been suffering from the disease since 2011 and only recently returned from Cuba, where he had been undergoing treatment.
One of the last photos taken of Hugo Chavez with his daughters, Maria Gabriela (left) and Rosa Virginia in Cuba
In an emotional statement, vice president Nicolas Maduro, flanked by leading politicians and military figures, announced the death of 58-year-old Chavez on national television.
"We have received the toughest and tragic information that... Commandante President Hugo Chavez died today at 4:25 pm," he said.
Earlier on Tuesday, Maduro had said that the president had a new, severe respiratory infection and had entered "his most difficult hours".
Chavez has been a divisive figure in Venezuela and beyond since winning the presidency in 1998. Last October, he won another six-year term in office but had been too ill to take the oath of office and when he announced he needed cancer surgery, he nominated Maduro as his successor if needed.
Only a few days ago, Maduro insisted that the president was not fighting for his life as he went through chemotherapy following the fourth cancer operation in December.
Speaking on Friday, Maduro said: "The treatments Commander Chavez is receiving are tough, but he is stronger than them."
William Hague said he was “saddened" to hear of Chavez's death.
“As president of Venezuela for 14 years he has left a lasting impression on the country and more widely. I would like to offer my condolences to his family and to the Venezuelan people at this time,” the foreign secretary added.
Venezuela and the USA had endured a difficult relationship since Chavez came to power, particularly whilst George W Bush was in the White House. On hearing the news of his death, president Barack Obama released a statement which emphasised the US's support for the Venezuelan people:
"At this challenging time of President Hugo Chavez’s passing, the United States reaffirms its support for the Venezuelan people and its interest in developing a constructive relationship with the Venezuelan government. As Venezuela begins a new chapter in its history, the United States remains committed to policies that promote democratic principles, the rule of law, and respect for human rights."
Some of Britain's left-leaning politicians took to Twitter to give their tribute to the president, including Respect MP George Galloway, who travelled to Venezuela during last October's elections to offer his support:
Former London mayor Ken Livingstone described Chavez as "a friend & comrade", adding that he "showed there is an alternative to neo-liberalism and colonialism in Venezuela and worldwide".
Chavez underwent surgery in Cuba in June 2011 to remove a tumour from his pelvic region but the cancer returned repeatedly in spite of three more operations, chemotherapy and radiation treatments.
Hugo Chavez met Ken Livingstone on a visit to London in 2006
Although hidden from the public for long periods, 'El Commandante', as he was known, kept in touch with the Venezuelan peopled through broadcast phone calls and Twitter, although the messages become more infrequent as his condition worsened. His last Twitter message was posted on 18 February 2013:
Which translated to English reads: "I still cling to Christ and trust in my doctors and nurses. Ever onward to victory! We will live and overcome!"
The election to find a new president is expected to be held within the next month and will pit Maduro against Henrique Capriles, the opposition leader who lost the October election to Chavez.
One recent opinion poll gave Maduro a strong lead. He enjoys support among many of the working class and could benefit from an inevitable surge of emotion in the coming days, Reuters reported.
However, the agency added that the president's death could also trigger in-fighting in a leftist coalition that ranges from hard-left intellectuals to army officers and businessmen.