The latest Brexit negotiations between the United Kingdom and the European Union remain at an impasse over the issue of the land border between Northern Ireland and the Republic of Ireland.

With leaders set to meet at the EU Summit on Wednesday in Brussels, the future of the so-called Withdrawal Agreement still hangs in the balance. If no deal is reached this week, a new emergency summit will be called for some time in mid-November.

"Brexit is probably the most unwise economic position that Europe has taken in the last 20 years along with the U.K.," said Adidas CEO Kasper Rorsted in a CNBC interview on Oct. 9. "There's no doubt that the consumer will be impacted and the economy will be impacted in the U.K., in Europe, for all businesses, including ours."

Here's what four experts had to say about how Brexit affects industries and markets.