The United States will not rest until justice is done in the downing of Malaysia Airlines Flight MH-17 over eastern Ukraine, President Barack Obama vowed in a condolence book for the nearly 300 victims. US lawmakers, meanwhile, pushed for a stronger response to the July 17 shootdown of the airliner over an area controlled by pro-Russia separatists. Obama visited the Netherlands Embassy in Washington to sign the book yesterday. Of the 298 people killed in the crash, 193 were Dutch. ‘No words can adequately express the sorrow the world feels over this loss. It is made more acute by the deep ties of friendship between our two countries,’ the president wrote in the book. ‘Bound by that friendship, we will not rest until we are certain that justice is done,’ he wrote. Obama later left on a three-day trip to Washington state and California that will be dominated by fund-raisers for Democratic congressional candidates. Congress members pushed for tougher action. The Democratic leaders of the US Senate’s national security committees called on Obama to impose immediate broad sanctions on Russia’s defense industry, including the state-owned arms exporter Rosboronexport. Senators Dianne Feinstein, Carl Levin and Robert Menendez also wrote to Obama, urging him to consider broader sanctions on Russia’s energy and financial industries and any other appropriate sectors of its economy to penalize Moscow for supporting the separatist rebels and express outrage over ‘the wanton destruction’ of the flight. Georgia Republican Saxby Chambliss issued a statement saying Washington should give stronger military assistance to the Ukrainian government if Moscow does not withdraw support for the separatists.