US would look to Germany for leadership after Brexit, former ambassador says

The United States is likely to forge closer ties with Germany if the United Kingdom leaves the European Union, former U.S. Ambassador to NATO Nicholas Burns said Tuesday.

American leaders have long looked to the U.K. to "translate" the EU, said Burns, now a professor at the Kennedy School of Government and an adviser to Hillary Clinton. The two countries share a "tough-minded" view of the world, he added.

Germany is the country most likely to fill the void left by the U.K. if the country's leaders act on last week's referendum to leave the EU.

"If the British leave, then the United States is going to have to have a country with which it works very closely on all these important trade and political and security issues. That country is going to be Germany," Burns told CNBC's "Squawk Box."

That is because Germany is the largest economy in the EU and Chancellor Angela Merkel is the most respected leader on the continent, he said. He acknowledged Merkel's popularity had taken a hit due to her push for European countries to quickly admit Syrian refugees, but said Germany still remains the de facto leader of Europe.

European leaders are gathering in Brussels to discuss Britain's possible exit from the union. On Tuesday, Merkel warned the U.K. it should not expect to reap the benefits of the single European market free of the obligations of membership, The Wall Street Journal reported.

British Prime Minister David Cameron has said he will not invoke Article 50 to begin the process of leaving, but Burns said European nations do not want to set precedent of allowing members to drag out their exit.

Burns does not expect other EU members to follow suit unless nationalist parties win a controlling majority in those countries, and that outcome is not likely in his view.