Rail, air and sea services between the UK and France resumed on Wednesday morning after France eased its travel ban.
French citizens, British nationals living in France and hauliers are among those now able to travel - if they have a recent negative Coronavirus test.
The Netherlands and Belgium have also relaxed bans on arrivals from the UK, as long as they have a recent negative result.
But more than 50 other countries, including Germany, Italy, India and Pakistan, are continuing to block travellers from the UK.
The travel ban was imposed on Sunday after the UK government warned of a new, fast-spreading variant of Coronavirus.
Some passengers have been stuck on the UK side of the channel for several days due to a massive logjam in mostly freight traffic in and around Dover.
“While it is important to take swift temporary precautionary action to limit the further spread of the new strain of the virus and all non-essential travel to and from the UK should be discouraged, essential travel and transit of passengers should be facilitated” European Commission statement
More than 3,000 lorries remain stranded in Kent, unable to make the crossing to France, with drivers having spent a second night sleeping in their cabs.
This has all added to the growing pressure on UK Prime Minister Boris Johnson who is still trying to clinch a trade deal with the EU before the end of the transition period on 31 December.
Many see the recent travel chaos at UK ports as a “dress rehearsal” for what could happen if there is a No Deal.
The European Commission has urged other Member States to lift travel banks affecting the UK, but said non-essential travel should be discouraged.
On Tuesday, the Commission issued a statement that said, “Following the rapid increase of COVID-19 cases in parts of England, of which a large proportion belongs to a new variant of the virus, the Commission has adopted a Recommendation on a coordinated approach to travel and transport measures.”
“The recommendation builds on the Council recommendation of 13 October on a coordinated approach to free movement in response to the COVID-19 pandemic and several other guidance documents adopted by the Commission in the past months, in particular the Green Lanes Communication.”
“Many see the recent travel chaos at UK ports as a 'dress rehearsal' for what could happen if there is a No Deal”
“While it is important to take swift temporary precautionary action to limit the further spread of the new strain of the virus and all non-essential travel to and from the UK should be discouraged, essential travel and transit of passengers should be facilitated.”
It adds, “Flight and train bans should be discontinued given the need to ensure essential travel and avoid supply chain disruptions.”
Until the end of December, free movement rules still apply to the UK. This means that Member States should not, in principle, refuse the entry of persons travelling from the UK.
Speaking on Tuesday, EU Commissioner for Justice, Didier Reynders, said, “Given the current uncertainties and in light of the precautionary principle, Member States should take coordinated action to discourage non-essential travel between the UK and the EU.”
“At the same time, blanket travel bans should not prevent thousands of EU and UK citizens from returning to their homes.”
“While precautions are needed to contain the spread of the new Coronavirus variant, with today's Recommendation, we therefore ensure that the restrictions are coordinated and provide the necessary exemptions for citizens and residents returning home and other essential travellers.”
His comments were echoed by EU Commissioner for Home Affairs, Ylva Johansson, who said, “To be effective, our actions must be coordinated and today we are facilitating swift action to address the new Coronavirus variant while ensuring that essential journeys can still take place.”
More comment came from EU Transport Commissioner Adina Vălean, who noted “Within the EU, it is crucial that transport workers are exempted from any restrictive measures, as quarantine and testing. We have to continue to maintain the supply chains intact, in line with our Green Lanes Communication.”