Russia threatened to take "reciprocal measures" if Secretary of State Rex Tillerson's visit to Moscow doesn't alleviate "irritants" plaguing the former Soviet power, in a preview of his trip.

"The long list of irritants [created] by Washington has not become shorter yet," the Russian Foreign Ministry said in a statement on Tillerson's arrival. "Since nothing is being done to settle the problems in bilateral relations, we will have to take reciprocal measures."

Russian Foreign Minister Sergey Lavrov's aides adopted a rather heated tone throughout the statement on his trip, effectively revising a milder preview that was released prior to President Trump's decision to retaliate against Syrian President Bashar Assad's use of chemical weapons. Where the Russian government had been content to blame former President Barack Obama for the breakdown in ties with the west, the new statement attributed a host of foreign policy problems to American mistakes.

"Overall, we hope that the US Secretary of State will share with us Washington's views on all issues of mutual concern," the statement said. "We are ready for any turn of events. However, we would prefer our interaction to help reduce rather than aggravate international tensions. We are not set for confrontation but for constructive cooperation and hope that this is what our American partners want, too."

Trump's team had hoped to cooperate with Russia to defeat Islamic State in Syria, but the latest chemical weapons attack prompted U.S. leaders to issue sharp denunciations of Putin's government. Russia, as Assad's chief backer, was supposed to guarantee the removal destruction of his chemical weapons stockpiles under the terms of a 2013 international deal.

"It is unclear whether Russia failed to take this obligation seriously or Russia has been incompetent, but this distinction doesn't much matter to the dead," Tillerson said. "We can't let this happen again."

British Prime Minister Theresa May, after speaking to President Trump, expressed hope that Tillerson can convince Russia to stop backing Assad. "The prime minister and the president agreed that a window of opportunity now exists in which to persuade Russia that its alliance with [Syrian President Bashar] Assad is no longer in its strategic interest," a May spokesman said Monday.

Assad has provided Russia a control of a naval facility in Tartus, Putin's only port on the Mediterranean Sea. A January agreement gave Russia sovereignty over the facility and the authority to expand the port so that it can hold up to 11 nuclear-powered combat ships.

"Russia will not abandon its legitimate interests and will only cooperate on an equal basis, which does not please certain forces in Washington," Lavrov's team warned Tuesday. "We have always been open to candid dialogue with the United States on all issues on the bilateral and international agenda and for cooperation in the areas where we have similar goals."