A top Chinese official has rubbished claims circulated on social media that the locomotives used to propel trains on the standard gauge railway are refurbishments of old models.
China's vice-minister for Foreign Affairs Zhang Ming said his country abhors the export of any used item and that there was no chance that a previously used machine could find its way to Kenya.
At a press briefing with Kenyan and Chinese journalists at a Nairobi hotel, Mr Zhang, who was China's ambassador to Kenya between 2006 and 2009, said the source of the claim of using second-hand locomotives was "understandable because, in Kenya, we see many people sell old cars and even second-hand clothes".
"Let me assure you that China never exports second-hand clothes; we never export second-hand cars and it is by no means possible for us to export second-hand locomotives," he said through a translator.
Images shared on various social media platforms depict an old locomotive juxtaposed with the ones that are being used to propel the new trains, with some suggesting that the old engine was refurbished and brought to Kenya.
But Mr Zhang said it would not make sense to have a used one.
"For the Chinese, it makes more economic sense to build a new locomotive instead of using our energy and using our input to refurbish the old one, because refurbishing needs more energy than building a new one in China," he said.
Mr Zhang spoke a day after President Uhuru Kenyatta made his inaugural trip on the train, dubbed Madaraka Express.
Mr Kenyatta said the launch was the beginning of Kenya's transformation.
The first phase of the construction has cost Sh327 billion, all in debt from the China Exim Bank.
On Wednesday, National Super Alliance (Nasa) presidential candidate Raila Odinga stepped up his criticism of the project's pricing, wondering why a Sh227 billion tender awarded during his tenure as Prime Minister was inflated to Sh350 billion.
Another Sh150 billion will be needed to extend the rail to Naivasha and another Sh370 billion to route it from Naivasha to Kisumu.
The debt implications on Kenyans have left critics talking.
But Mr Zhang said the debt issue "is not something we should be worried about".
"If we put the money from the debt in the right place, it is no problem for us to repay the debts. Apart from repaying the debts, the outcomes created by the debt might help to enhance development, create more jobs and add more fiscal revenue," he said.
At the press conference, a Chinese journalist asked whether Kenya had received an outdated train system with a top speed of averagely 100 kilometres per hour while trains in China go up to 300kph.
Mr Zhang answered that it was not all parts of China that had high-speed rail, saying that a system akin to the standard gauge rail is in use in many parts of China.
"We cannot say that the medium-speed rail is something that is outdated. The construction of the railway is an economic activity that should follow the principles of economy.
"And when deciding what kind of railway we should build, we should take into consideration the local reality and development needs," Mr Zhang said.