GENEVA (Reuters) - The U.N. children’s agency UNICEF said on Friday it was seeing clear signs of a growing malnutrition crisis in Venezuela, but it lacked data to give precise information and to tackle the problem effectively.

“While precise figures are unavailable because of very limited official health or nutrition data, there are clear signs that the crisis is limiting children’s access to quality health services, medicines and food,” UNICEF spokesman Christophe Boulierac told a regular U.N. briefing in Geneva.

Venezuela’s government has not published data on wasting - a low weight to height ratio in children under five - since 2009, when the figure was 3.2 percent. Aid agency Caritas put the figure at 15.5 percent last August, UNICEF said.

“When it’s about fighting child malnutrition, it’s not a time for discussing, it’s time for action,” Boulierac said. “Acting to fight malnutrition requires data, and there’s not enough official data right now and there’s not enough coordination.”

He said he had no information to suggest that UNICEF was being prevented from doing its work, and it was not uncommon to have a lack of data.

The government of President Nicolas Maduro says Venezuela is fighting a U.S.-led right-wing conspiracy determined to end socialism in Latin America, hobble Venezuela’s economy, and steal its oil wealth.

But critics say Maduro, who succeeded Hugo Chavez in 2013 and said this week he was standing for re-election, has ruined a once prosperous oil economy, turned Venezuela into a dictatorship and skewed the election system to perpetuate power for his Socialist Party. [nL2N1PJ14H]

UNICEF said the government had taken steps to mitigate the impact of the crisis on children, by providing affordable food packages to the most vulnerable families, cash transfers, and strengthening nutritional assessment and recuperation services.

But Boulierac said that without concerted action between the government, aid agencies and the U.N., efforts to tackle malnutrition would be ineffective.

“It’s a situation where there is an economic crisis, hyperinflation, sky-rocketing prices, and it’s also a socio-political crisis with a lack of agreement, dialogue, to solve the most urgent issues.”