U.S. business leaders were expected to air concerns over rising tensions with Russia and possible sanctions over its moves to annex Crimea, in a meeting with President Barack Obama's defense secretary and trade representative. U.S. Defense Secretary Chuck Hagel and U.S. Trade Representative Michael Froman were due to address chief executive officers and other businessmen, and answer their questions, at the Business Roundtable's quarterly meeting in Washington. The Obama administration has curtailed contacts with Russia since the Ukraine crisis blew up, and Froman earlier this month halted his agency's talks on deeper trade and investment ties with Moscow. The United States and Russia had started talking about a bilateral investment treaty, and Russian Economy Minister Alexei Ulyukayev said in February the next step would be a meeting of trade experts. A Pentagon spokesman said on Wednesday that Hagel was slated to discuss the Pentagon budget at the closed meeting but was prepared to address the Crimea crisis after President Vladimir Putin declared the Ukrainian region would become part of Russia. "No doubt in the context of the discussion, current events will come up," Rear Admiral John Kirby said. Hagel is standing in at the event for Vice President Joe Biden, who is traveling in eastern Europe to reinforce U.S. commitment to its allies. The Washington-based Business Roundtable is an association of chief executives of major U.S. corporations with global footprints, from the defense industry and consumer manufacturers to the healthcare and technology sectors. Randall Stephenson, chairman of the group and CEO of AT&T , told reporters on Tuesday that companies were closely watching the Ukraine crisis. U.S. and Europe on Monday imposed sanctions on Russian and Crimean individuals linked to the region's seizure. Russia scoffed at the sanctions but said it would retaliate, and the White House said more sanctions were to come. Sanctions & Retaliation Some critics said the sanctions were too weak to deter Putin, while others expressed concern about potential economic impact the sanctions and expected retaliation by Moscow could have on markets and trade. The trade of goods between Russia and the United States was worth $38.12 billion in 2013. U.S. firms have $14 billion in direct investment in Russia, with about half that amount coming the other way. Asked whether chief executives were concerned about a possible trade war, Stephenson said: "Anybody doing business in Europe is watching the situation very, very closely. It's obviously an area of concern." It was not immediately clear which CEOs would attend the meeting or what specific concerns they might raise. Representatives for several member companies said their CEOs were not attending the gathering. Others declined to comment on the private meeting. The Chamber of Commerce, another Washington-based business group, said it was closely monitoring the crisis over Crimea and called for close cooperation with Europe given it's annual trade with Russia is about 15 times larger than that of the United States. "A go-it-alone approach by the United States could be both economically damaging and ineffective in accomplishing its goals," said the Chamber's Vice President Myron Brilliant, who oversees international affairs for the group. Russia only joined the World Trade Organization in 2012 and so far has had no trade disputes with the United States, although U.S. trade officials in December raised concerns over vehicle fees, copyrights and a meat additive ban. Oil major ExxonMobil and aircraft maker Boeing are among the U.S. companies with strong links to Russia and who are involved in joint ventures with Russian partners. (Reuters)