Venezuela's vice president has flown to Cuba to visit the ailing Hugo Chavez and his family, while the leaders of Argentina and Peru also travelled to Havana saying they hoped to ask about the Venezuelan president's condition.
The 58-year-old president is fighting a severe respiratory infection a month after he underwent cancer surgery in Havana, his government said.
"I'm leaving for Havana to continue that work of visiting the family, meeting with his medical team, visiting our commander president," vice president Nicolas Maduro said on television in Caracas.
Cuba's nightly TV news show reported that Mr Maduro had arrived, but did not say whether he made any comments. The Venezuelan was met at the airport by Cuban foreign minister Bruno Rodriguez, the show said.
Mr Chavez has not spoken publicly or been seen since before his December 11 operation, his fourth cancer-related surgery since June 2011 for an undisclosed type of pelvic cancer. The government revealed this week that Mr Chavez is receiving treatment for "respiratory deficiency". Medical experts say that might mean he is breathing with the help of a ventilator.
Mr Maduro was making his second trip to Cuba since Mr Chavez's surgery. He said he would meet with Argentinian president Cristina Fernandez de Kirchner, who also was visiting Havana, and hoped to meet with Peruvian president Ollanta Humala, who arrived in the Cuban capital.
Ms Fernandez de Kirchner arrived at the Hotel Nacional along Havana's waterfront. Authorities have characterised the Argentine leader's trip as a private visit and her foreign minister said that she intended to meet with Mr Chavez.
She said she would lunch with Cuban president Raul Castro and his retired brother Fidel.
"And then surely I will meet with the family of my companion and dear friend Hugo Chavez," Ms Fernandez de Kirchner said.
Presidents Rafael Correa of Ecuador and Evo Morales of Bolivia have also visited Havana during Mr Chavez's current stay there.