The Herald newspaper added that the government had also called for the attackers - who appeared to be predominantly Zimbabwean - to be prosecuted after they splashed Moyo with bottled water while hurling insults at him at the Global Conference for Media Freedom, reported Xinhua news agency.
Moyo was on a four-day visit to the UK as part of the Zimbabwean government's re-engagement thrust, under which he sought to strengthen bilateral relations between the two countries and lure investors.
Acting Secretary for Foreign Affairs and International Trade Pavelyn Musaka on Tuesday said the government was concerned about the incident, while a source told the paper that inexplicable laxity by security services allowed the assailants to pounce, despite top-notch security having been provided prior to the incident.
"Our Government - through the Ministry of Foreign Affairs - has summoned the Charge d'Affaires of the United Kingdom, Great Britain and Northern Ireland, Mr Giles Enticknap, to register our government's protest against the assault on Minister Moyo and his Zimbabwe delegation to the Global Conference for Media Freedom co-ordinated by the government of the United Kingdom," she said.
"As organizers of the event, it was incumbent upon the Government of the UK to assess the threat level for all dignitaries and to provide under cover security details to protect Honorable Minister Moyo in the event of any unforeseen security situations arising.
"The Ministry wishes to inform our compatriots, members of the public that while Government of Zimbabwe respects the rights to freedom and the rights of its citizens to demonstrate peacefully as part of the democratic process be it here in Zimbabwe, in the UK or any part of the world that our delegations are invited to visit whether in their official capacity or in the personal capacities it objects to the assaults on Minister Moyo as head of the Zimbabwean delegation," she said.
She said the protesters' actions were a violation of laws of both the UK and international laws regarding the protection of persons of Moyo's stature.
"The Ministry therefore calls for the government of UK to take all measures necessary to bring the perpetrators of the violence against the minister to book for their actions," she said.
Following the attack, Moyo twitted to his followers saying that he was unharmed.
( With inputs from IANS )