Iran is planning to send another live monkey into space within a month, a top space official said in remarks reported by media Sunday.
"The second live animal will be ready within a month to be sent into space," said Hamid Fazeli, deputy head of Iran's space organisation, the Jomhuri Eslami newspaper reported.
Iran in January claimed to have successfully launched a live monkey into space and to have brought it safely back to earth.
The experiment's success was disputed, however, when a different monkey was presented to the media after the landing. An earlier attempt had failed in September 2011.
Iran's space programme has prompted concern among Western governments, which fear Tehran is trying to master the technology required to deliver a nuclear warhead.
Iran denies it is seeking nuclear weapons or the means to deliver them.
Fazeli said the monkey would be sent into space via "a liquid-fuel launcher," while refusing to set a "definite date" for the launch. Iran has delayed past launches without giving specific reasons.
Akbar Torkan, the interim chief of Iran's space organisation, said on Sunday the delays are due to budget woes.
"The decrease in the country's total revenue, and thus the budget, has impacted our space-related activities," Torkan was quoted as telling the official IRNA news agency.
Iran is under harsh Western-led international sanctions targeting its vital oil income and aimed at curbing its controversial nuclear drive.
Earlier this week, Fazeli said Iran would put three satellites into space by the end of the Iranian year, in March 2014.
The Islamic republic, which first put a satellite into orbit in 2009, has outlined an ambitious programme with plans to send a man into space within a decade.