President Barack Obama must beat back any Russian demands for "red-button" sway over a missile shield in Europe and deny Moscow access to sensitive data tied to the program, US senators urged Thursday.

The 39 lawmakers, all Republican foes of the White House, said in a letter to Obama that they were "concerned" Russia would exploit his desire for bilateral cooperation on the issue to "undermine" US national security.

The group, led by Republican Senator Mark Kirk, warned against giving Moscow any right to veto use of the shield or providing Russia with "access to America's most sensitive missile defense data and technology."

"No American President should ever allow a foreign nation to dictate when or how the United States defends our country and our allies," they said in the letter, which was obtained by AFP.

"In our view, any agreement that would allow Russia to influence the defense of the United States or our allies, to say nothing of a 'red button' or veto, would constitute a failure of leadership," they said.

The lawmakers said they had "serious concerns" over news reports that Obama was weighing providing Russia with sensitive satellite data or technology related to anti-missile interceptors.

"We therefore ask for your written assurances that your Administration will not provide Russia with any access to sensitive US data, including early warning, detection, tracking, targeting, and telemetry data, sensors or common operational picture data, or American hit-to-kill missile defense technology."

The senators urged the president to "make clear in every engagement with Russia that it will have no say in the location, capability or timing of U.S. missile defense deployments with a NATO military alliance."

"We trust this includes the location of interceptors in Europe, including in Romania and Poland, and missile defense radars, whether in Turkey, the Republic of Georgia, or another location that is most advantageous for the defense of the American people," they wrote.