CARACAS (Reuters) - Venezuela's socialist President Nicolas Maduro announced on Sunday a 50 percent hike in the minimum wage and pensions, the fifth increase over the last year, to help shield workers from the world's highest inflation rate.

The measure puts the minimum monthly salary at 40,683 bolivars - about $60 at the weakest exchange level under the state's currency controls, or $12 at the black market rate.

"To start the year, I have decided to raise salaries and pensions," he said on his weekly TV and radio program.

"In times of economic war and mafia attacks ... we must protect employment and workers' income," added Maduro, who has now increased the minimum wage by a cumulative 322 percent since February 2016.

The 54-year-old successor to Hugo Chavez attributes Venezuela's three-year recession, soaring prices and product shortages to a plunge in global oil prices since mid-2014 and an "economic war" by political foes and hostile businessmen.

But critics say his incompetence, and 17 years of failed socialist policies, are behind Venezuela's economic mess.

They say the constant minimum wage hikes symbolize Maduro's policy failures and fail to keep pace with real on-the-street price rises.

Venezuela's inflation hit 181 percent in 2015, according to official data, though opponents say the true figure was higher. There is no official data for 2016, but most economists think inflation at least doubled from the previous year and will be worse again in 2017.

Venezuela's opposition has said inflation was more than 500 percent in 2016, while the economy shrank 12 percent. The government has given no gross domestic product data for last year.

(Reporting by Diego Ore; Writing by Andrew Cawthorne; Editing by Alan Crosby)