IRNA � United Nations Secretary General Antonio Guterres congratulated Muslims across the world on the arrival of fasting month of Ramadhan late on Sunday.

In a tweet in the Arabic and English languages, he wrote Happy Ramadhan to all Muslims.

He hoped that virtues of the holy month, mercy and forgiveness would be a source of inspiration for all.

Some Arab states, including Saudi Arabia, Kuwait, Bahrain, UAE, Qatar, Lebanon and Libya have declared Monday (May 6) as the first day of fasting month of Ramadhan.

Ramadan is the ninth month of the lunar Islamic calendar. During Ramadan, observant Muslims abstain from eating, drinking and smoking from dawn to dusk.