Breaux, LottFormer Democratic Senator John Breaux of Louisiana and Republican Trent Lott of Mississippi are trying to torpedo US sanctions against Russian natural gas giant Gazprom to punish Vladimir Putin for his invasion and possible annexation of eastern Ukraine.

President Obama today accused Russia of launching a "brazen assault on the territorial integrity of Ukraine, a sovereign and independent European nation."

He spoke from Estonia, a front-line Baltic state with a big Russian minority population similar to Ukraine.

The European Union, which slapped a ban on raising capital in its markets on Russian state banks, may extend it to Russian state companies including Gazprom.

Gazprom supplies Europe with a third of its natural gas. Putin has launched a drive to step up natural gas exports to China

Gazprombank, the financial arm of Gazprom, are paymasters of Breaux and Lott for their anti-sanctions work, The duo are at Squire Patton Boggs.

Ketchum, which represents Putin and Russia, has done work for Gazprom.