A growing chorus of Capitol Hill lawmakers are urging France to scrap a lucrative deal to sell two high-tech warships to Russia as the country flexes its muscle in eastern Europe.

While the United States and its European allies have censured Russia for annexing Crimea from Ukraine, the warship contract highlights the political and economic difficulties of trying to isolate the country.

U.S. concerns about the deal are twofold: a worry that selling arms to Russia while condemning its military are contradictory, and a fear the warships will help it expand its military presence in eastern Europe.

"This ship is a threat to some of America's friends and NATO allies," said Sen. John McCain, R-Ariz., a member of the Senate Foreign Relations Committee. "I worry that this decision could set a troubling precedent within NATO of advanced weapons sales to the Russian government."

France has completed the first of two Mistral-class helicopter carriers for the Russian navy at a cost of $1.65 billion. This month 400 Russian sailors arrived in France to be trained how to operate the giant vessel, the Vladivostok, before sailing it home in the fall.

In Congress, lawmakers from both parties and chambers have urged France to cancel the deal through direct appeals to French President Francois Hollande, NATO -- which also opposes the deal -- and the Obama administration.

“The NATO Alliance cannot continue to arm Russia -- let alone arm her with high-tech military equipment that will only abet its efforts to undermine Eastern European governments that aspire to be modern, European democracies,” Sens. Mark Warner, D-Va., and Mark Kirk, R-Ill., and Reps. Adam Kinzinger, R-Ill., and Bill Keating, D-Mass., wrote in a letter to Obama.

“France, and all NATO allies, must make tough choices when responding to this new, aggressive Russian foreign policy.”

The U.S. and the European Union, of which France is a key member, have imposed sanctions against Russia, including travel bans and freezes of Russian officials' and business leaders' assets. But they have held off on tougher penalties.

French leaders acknowledge the deal puts them in a tricky spot, as they simultaneously balance sanctioning Russia while seeking to boost France’s struggling defense industry.

With a stagnant economy and an unemployment rate above 10 percent, France is desperate to establish trade deals with a big-time client like Russia. The deal means about 1,000 jobs for France. And Russian President Vladimir Putin has hinted at future military contracts with France -- as long as it gets the two ships.

France isn't alone. Italy recently sold armored vehicles to Russia. And a German defense company was in a contract to build a military training facility there until the German government halted the project, at least temporarily, after the Crimean crisis.

Obama said that while he recognizes the economic importance of the deal to France, “it would have been preferable to press the pause button.”

"President Hollande so far has made a different decision," he said.

Sen. Lindsey Graham, R-S.C., said it's Obama, not Hollande, who is most to blame for not pushing back at Putin.

“The French — everybody’s doing what they think’s best. [But] there is no American leadership here,” he said. “I think if we’d come down hard on Russia the French would’ve probably been under pressure to break the deal.”

A trio of House members have suggested a compromise to France: sell or lease the ships to NATO.

“Such a purchase would rapidly enhance NATO capabilities at a moment when many [U.S. European] allies have been cutting defense expenditures," said Reps. Eliot Engel, D-N.Y., Michael Turner, R-Ohio, and Keating in a letter last month to NATO Secretary General Anders Fogh Rasmussen.

But for now, France says it won't back out of the deal.

“We are executing the contract in full legal compliance because we’re not at that level of [tougher] sanctions” with Russia, Hollande said this month.