The UK and French governments have reached a deal to reopen the border between the two countries to hauliers and some passengers from Wednesday - if they test negative for COVID.
As part of the agreement, the military and NHS Test and Trace teams are to establish multiple testing sites in Kent.
Quick turnaround tests will be deployed in an effort to get moving the more than 2,800 lorries that have been left trapped in Kent, but the queues built up around motorways could still take days to clear.
Rail, air and sea services will now resume on Wednesday morning, with all those travelling from the UK into France required to show proof of a negative coronavirus test taken within the previous 72 hours.
Transport Secretary Grant Shapps revealed on Tuesday evening that the French government had agreed to accept lateral flow tests, which can return results in around 30 minutes, in order to get freight traffic moving again.
"We've made good progress today with the French government and what we've agreed is the border can open with tests for everybody leaving the country," Mr Shapps said, following talks with French officials throughout the day.
"That means you must have had a test within the last three days and, of course, it's got to be a test which is certified as well."
A delay in securing an agreement on resuming cross-Channel travel earlier in the day was believed to have related to French concerns over the accuracy of the pregnancy-style lateral flow tests.
Alternative PCR tests can take 24 hours to return a result.
Despite the border agreement, Mr Shapps urged other hauliers to stay away from Kent until there are further announcements.
"It's very important hauliers don't rock up in Kent tonight, there's nowhere for you to go, it won't speed up your crossing of the Channel, stand by and await more instructions," he added.
The transport secretary said enough tests had been sent to Kent for the current number of drivers waiting on or near motorways.
But he warned that, due to the operational challenges of providing the tests and receiving results, that it will take "two or three days for things to be cleared".
Asked how long it might be before a normal flow of freight traffic resumes in Kent, Mr Shapps added: "What we'll aim to do is have this cleared either by Christmas or perhaps in that little period between Christmas and New Year."
The agreement with France will be reviewed on 31 December, but could run until 6 January, the Department for Transport said.
Under the deal, entry into France will only be granted to those travelling for urgent reasons - including hauliers - French citizens, and British citizens with French residency.
The French government will also carry out sample testing on incoming freight to the UK.
The Department for Transport said the full details of the protocol - including what would happen to EU lorry drivers waiting in Kent who might test positive - would be published on Wednesday.
France's transport minister, Jean-Baptiste Djebbari, earlier thanked Mr Shapps on Twitter for the "amazing work we have done" over the past 48 hours.
The border deal comes after Prime Minister Boris Johnson and French President Emmanuel Macron spoke on Monday, with UK and French officials having worked to reach an agreement to unlock the ban on Tuesday.
The disruption on the South Coast had seen the M20 motorway in Kent closed on Monday night to allow the implementation of Operation Brock.
The action, which involves using a moveable barrier to keep traffic moving on the motorway whenever there is disruption at the Channel, had been prepared for possible Brexit delays early in the New Year, but was called upon early.
More than 600 lorries were queued on the M20 by Tuesday evening, with 2,180 more forced to wait at a former airfield site in Manston, Kent.
Many lorry drivers had spent a second night sleeping in their cabs as they awaited news of a decision on the border.
France was among more than 40 countries around the world to have implemented travel restrictions on the UK due to the mutant variant of coronavirus, which spreads more readily than previous strains.
UK supermarkets have warned of shortages of some fresh fruit and vegetables if the disruption continues.
Ian Wright, chief executive of the Food and Drink Federation, said that while shoppers "need have no concerns about food supplies over Christmas", the consequences could be felt soon after.
The European Commission had earlier on Tuesday urged member states that have restricted travel from the UK to lift their bans to allow essential travel and minimise trade disruption.