Egyptian government fighter jets struck militant training bases in neighbouring Libya in retaliation for the incident.
President Abdel-Fattah el-Sissi said planes have targeted sites responsible for the training of those behind the shooting which targeted a bus south of Cairo on Friday.
During a televised address, he also urged the US President to lead to the fight against global terror, saying: "I direct my appeal to President Trump: I trust you, your word and your ability to make fighting global terror your primary task."
Witnesses said between eight and ten attackers wearing masks and military uniforms opened fire on the bus, which was travelling along a desert road leading to a remote monastery.
The vehicle contained pilgrims bound for the monastery of St Samuel the Confessor in Maghagha, Minya, approximately 140 miles south of Cairo.
No group has yet claimed responsibility for the attack - which also left 22 other people wounded; however, it bears the hallmarks of Islamic State.
Egyptian officials say warplanes targeted the headquarters of the Shura Council in Darna, eastern Libya, where militias are known to have ties with al Qaida but not IS.
Friday's attack in Minya marks the fourth deadly attack to target Christians since December last year. Two suicide bomb attacks at churches in Alexandria and Tanta left 45 people dead on Palm Sunday.
A suicide bombing at a chapel next to St Mark's Coptic Orthodox Cathedral in Cairo on 11th December 2016 killed 29 people.
During his televised address, Mr el-Sisi said Egypt would target any locations training militants to attack the country. He also said countries funding, training or equipping extremists should be punished.