BANGKOK, March 8 (Xinhua) -- Thailand will use brand-new banknotes with a portrait of newly-succeeding King Rama X on the front of the baht bills from next month.

Bank of Thailand Governor Veerathai Santiprabhob announced on Thursday the Series 17 banknotes, which will be issued under permission of King Maha Vajiralongkorn, show the portrait of the new monarch in Air Force marshal uniform on the front and those of previous kings on the back.

The new 20-baht, 50-baht and 100-baht banknotes will be issued on April 6, which marks Chakri Memorial Day in commemoration of King Maha Vajiralongkorn's Chakri Dynasty, while the new 500-baht and 1,000-baht bills will be issued on July 28, which marks the new king's birthday anniversary.

The portraits of King Rama I and King Rama II are on the back of the 20-baht banknote, those of King Rama III and King Rama IV on the back of the 50-baht banknote, those of King Rama V and King Rama VI on the 100-baht banknote, those of King Rama VII and King Rama VIII on the 500-baht bill and those of King Rama IX and King Rama X on the 1,000-baht bill.

All existing baht bills will remain valid and exchangeable as usual, according to the central bank's governor.