HAVANA: Venezuela's vice president is back in Havana to see cancer stricken Hugo Chavez, as an opposition leader called for the once ever-present president to speak out and give his people peace of mind.

Nicolas Maduro traveled to Cuba late Wednesday after a day of dueling marches in Caracas: tens of thousands demonstrated in support of Chavez, overshadowing a much smaller rival rally by the opposition.

Chavez has been convalescing in Cuba since his latest surgery last month, but his condition is improving, according to Caracas.

Opposition leader Henrique Capriles, who lost to the 58-year-old Chavez in October's election, challenged the ailing leader to speak to the nation if he is able, saying the Venezuelan people deserve "peace of mind."

"The government has said that the president is walking, that he is joking. So why does he not speak to the nation and give some peace of mind to his followers and all Venezuelans?" he said.

Chavez supporters -- clad in red shirts bearing the phrase "Chavez is all of us" -- however seemed to need no reassurances about their president's prolonged absence from the oil-rich South American country.

Bearing flags, crosses, and pictures of Chavez and independence hero Simon Bolivar, pro-government demonstrators converged on the capital's January 23 neighborhood for the main rally.

Both Chavistas and the opposition rallied to celebrate the anniversary of the 1958 ousting of Venezuela's last dictator, Marcos Perez Jimenez. But the marches reflected the tension of the current political crisis.

"The goal is to confirm the people's commitment to President Chavez, to support him wherever he may be, however he may be, and so the world will know that the seed he planted is growing and will continue to grow," Audrey Ramirez, 43, a state bank employee, told AFP.

Chavez, who had surgery on December 11, was too sick to attend his January 10 inauguration, prompting the government to delay the swearing-in indefinitely under an interpretation of the constitution criticized by the opposition.

The Chavez-controlled National Assembly and Supreme Court both approved the arrangement, which keeps his administration in place under Maduro until Chavez can take the oath of office for his fourth term.

On Monday, Foreign Minister Elias Jaua had said after a visit with Chavez that the president has been talking with aides, giving orders and cracking jokes.

Capriles, the governor of Miranda state, flatly charged that the executive branch was "lying and toying with people's hope," and urged Chavez to return home and govern as he was elected to do.

Chavez, an anti-US firebrand leftist, is known for filling up hours of state media time a day with his own speeches, ceremonies and personal reflections.

Most analysts believe Capriles would be the opposition candidate to take on Maduro, Chavez's self-appointed successor, if the president were unable to govern.

Maduro said Wednesday Chavez would return home sooner rather than later.

He said he and oil minister Rafael Ramirez, who traveled with him, would take to Chavez "the love and greetings" of the people and take turn keeping Chavez and his family company.

The government also charged Wednesday that right-wing extremists were plotting to attack Maduro.

"We have received some very important intelligence in which actors from Venezuela's extreme right, working with right-wing actors from outside the country, were plotting an attack against the vice president" and National Assembly speaker Diosdado Cabello, said Interior Minister Nestor Reverol.

"Anyone who makes this mistake will go to prison. Anyone who violates the Constitution ... will go to prison. We have a hard line against right-wing conspiracy," Maduro said.