Switzerland is not in the customs union, while France is, however, there is no such border in sight.
This is how the border between Northern Ireland and the Republic of Ireland may be under the Prime Minister's ladies plan, but the EU wants a "hard" border if Northern Ireland leaves the customs union.
Philip wrote on Twitter: "This is what the border of the EU Customs Union may look like: Flughafenstrasse in Basel on the Swiss (not CU) French border (in CU).
"There is a small signal and a small camera of the type that you see on all the main streets. There are technical solutions to ensure that there are no hard NI / RoI borders. "
This happens when Theresa May states that 95 percent of the British agreement with Brexit has been agreed, apart from the Irish border solution.
With little more than five months until Britain is scheduled to leave the EU, the talks have been stalled by a disagreement over the so-called "backing" of Northern Ireland.
The insurance policy is a proposal to guarantee that there will be no return to a hard border on the island of Ireland if a future commercial relationship is not agreed on time.
However, for an agreement to take place, this will have to be agreed with the EU's chief negotiator, Michel Barnier. But last week, the EU ruled that "not enough progress has been made" in the talks on Brexit at the EU summit in Brussels.
The secretary of Brexit, Dominic Raab, spoke in support of the Prime Minister and believes that there is a "good agreement" in sight.
Mr. Raab said: "I think it is understandable that there is nervousness on all sides of this debate and we have to keep our nerves going."
"The end is in sight in terms of a good agreement, the prize we want, a good agreement with the EU and I think colleagues should wait and see what it looks like.
"We do not want to return something that we do not trust is good business for the United Kingdom."
Ms. May received strong criticism after proposing the idea of extending the transition period "for a few months" beyond the current 21-month plan.
The current transition period must end on December 31, 2020.
Union leader Jeremy Corbyn described Ms. May's negotiation skills "a disaster" after failing to reach an agreement.
She said: "The prime minister has got into this mess by not achieving any meaningful agreement with the EU."