The Zika virus is expected to spread to Europe by the summer.
The likelihood of local Zika transmission if no preventative action is taken is "moderate" in 18 countries, the World Health Organisation (WHO) said.
While the UK is deemed to be "low" risk, global health chiefs have urged people to be prepared.
Officials will also continue to be alert to detect imported cases early and provide public health advice to travellers.
WHO said the risk is higher where the mosquito that carries the virus is present such as the island of Madeira and the north-eastern coast of the Black Sea.
Dr Zsuzsanna Jakab, WHO regional director for Europe, said: "With this risk assessment, we at WHO want to inform and target preparedness work in each European country based on its level of risk.
"We call particularly on countries at higher risk to strengthen their national capacities and prioritise the activities that will prevent a large Zika outbreak."
The Zika virus, which is known to cause birth defects, is currently present in 58 countries.
The most recent figures show that 23 UK travellers have been infected after visiting affected regions.