"He is deeply disturbed by the increase in deaths and serious injuries," said Stephane Dujarric, Spokesman for the Secretary General, in a statement on Sunday.
According to the spokesperson, the use of lethal force against peaceful protestors and arbitrary arrests are unacceptable.
"The Secretary-General urges the international community to come together and send a clear signal to the military that it must respect the will of the people of Myanmar as expressed through the election and stop the repression," the spokesman stated.
The military has claimed, without evidence, that the ruling party of State Counsellor Aung San Suu Kyi – the National League for Democracy (NLD) – fraudulently won parliamentary elections.
Arrested on February 1, she and other leaders have remained in detention and according to news reports she is due in court on Monday.
On Friday, the UN Ambassador to Myanmar Kyaw Moe Tun denounced the coup in a UN General Assembly meeting in New York, calling on the international community to take the strongest possible measures against the military junta to restore civilian rule.
The top diplomat was reportedly fired from his post on Saturday.