A number of countries have strongly condemned the bombing of a tourist bus on Friday in Giza which killed four people, including three Vietnamese tourists.
Vietnam called on Egypt to find the perpetrators, Reuters reported.
"Vietnam is extremely angered by and strongly condemns this act of terrorism that killed and injured innocent Vietnamese people," Foreign ministry spokeswoman Le Thi Thu Hang said in a statement according to Reuters.
"Vietnam requests that Egypt promptly launch an investigation into the case and track down those responsible.”
One Egyptian tourism worker on the bus was killed during the explosion, which was caused by an IED, while 11 Vietnamese were injured.
In a tweet, British Foreign Office Minister for the Middle East Alistair Burt said he was "deeply saddened to hear of the loss of life following the bomb attack on a tourist bus in #Giza #Egypt. My thoughts are with the victims and their families."
"The UK supports Egypt in their fight against terrorism," Burt said.
UK's Ambassador to Egypt Sir Geoffrey Adams also tweeted to offer his condolences to Egyptians for the attack.
"Our hearts go out to the families of the victims and all those affected in today’s incident in Giza, and to the Egyptian authorities as they respond," adding that "the UK stands with Egypt in the fight against terrorism."
The US also strongly condemned the attack in a statement issued by the State Department’s Deputy Spokesperson Robert Palladino.
"The United States strongly condemns the attack carried out today on a tourist bus in Giza," the statement said. "Our deepest condolences go out to the families of those killed and we wish a quick recovery for those injured."
"We stand with all Egyptians in the fight against terrorism and support the Egyptian government in bringing the perpetrators of this attack to justice."
Ambassador of the European Union delegation to Egypt Ivan Surkos tweeted: "I strongly deplore an attack on a bus carrying tourists in Giza that happened a while ago, resulted in death and casualties of innocent people."
Surkos stressed that the "#EU stands hand in hand with #Egypt in the fight against terrorism." He has also offered condolences to families of victims.
Kuwait's Emir Sheikh Sabah Al-Ahmad Al-Jaber Al-Sabah also expressed his condolences to Egypt's El-Sisi, according to the official Kuwaiti News Agency (KUNA).
Al-Sabah expressed his country's "robust denunciation of this horrific terrorist act that targeted the innocent and aimed at jeopardising Egypt's security and stability".
Al-Sabah stressed that his country will support Egypt in all measures which will be taken to secure the safety and the stability of the country.
Egypt's Prosecutor-General Nabil Sadek announced on Friday night that three Vietnamese and one Egyptian had died in the attack.
The explosion occurred when an IED detonated as the tourist bus was moving along Maryoutiya Street in the Haram district of Giza; 14 Vietnamese tourists and two Egyptian tourism workers were on board.