The consumer price index (CPI) of Vietnam rose 3.29 percent on-year in the first half of 2018, the country's General Statistics Office announced on Friday.

In June alone, the index increased 0.61 percent against May, and climbed up 4.67 percent against June 2017.

The higher CPI in June was mainly caused by higher prices of oil and petrol products, construction materials and educational services, said the office.

Also, hot weather led to higher demand, and consequently, prices of household water and electricity increased.

In the six-month period, telecommunications charge was the only item which experienced a decline of 0.61 percent on-year.

In 2017, Vietnam's CPI rose 3.53 percent compared to 2016, far below the 4-percent target set by the country, said the office.