WASHINGTON (Reuters) - Nine senators from his own Republican party urged President Donald Trump on Thursday to take a “tough-minded” approach to Russia, joining a growing chorus of lawmakers addressing concerns that he might be too conciliatory toward Moscow. The nine senators, including the Senate’s number two Republican, John Cornyn, wrote in a letter to Trump that cooperation with Moscow is essential in many areas, but calling for tough action on Ukraine, Syria and cyber security. “However, while we should seek common ground with Russia in the areas of mutual interest, we must never pursue cooperation with Russia at the expense of our fundamental interests of defending our allies and promoting our values,” they wrote. The letter said the United States should condemn, and take steps to stop, Russian aggression in Ukraine, including maintaining sanctions and imposing new ones as necessary. They also want Trump to send Ukraine lethal weapons to defend itself. Trump’s open admiration for Russian President Vladimir Putin and promises to rebuild frayed U.S. ties with Moscow have raised questions, in Washington and among U.S. allies, over his commitment to maintaining sanctions against Russia for its involvement in fighting in Ukraine and annexation of Crimea from Ukraine. The letter also said Washington should not enter into any agreement with Moscow on Syria until Russia stops supporting the government of Syrian President Bashar al-Assad. And it said Washington should counter cyber attacks blamed on Russia. The letter was led by Senator Cory Gardner. Besides Cornyn and Gardner, it was also signed by Jim Inhofe, Todd Young, Rob Portman, Mike Rounds, Joni Ernst, Susan Collins and Lindsey Graham. Republicans and Democrats in the Senate and House of Representatives have also introduced legislation seeking additional action against Russia, although there has been no action on most of those bills just three weeks into the Trump administration. Some lawmakers have also sought to give Congress a voice over whether Trump, who has issued a series of executive orders on a range of issues, can ease current sanctions on Russia. 