Truss said she would be travelling to Turkey on Wednesday to discuss options to help get grain out of Odesa, saying that there was only a matter of weeks to find a solution.
Britain, the United States and the European Union have coordinated in imposing massive sanctions on Moscow for what they call an invasion of Ukraine. Russian President Vladimir Putin has termed it a military operation.
"We will continue to impose sanctions, we will continue to stop importing goods from Russia until we see Russia fully withdraw from Ukraine," Truss said.
Britain has targeted Russian businessmen, politicians, religious leaders and businesses as part of its wide-ranging sanctions on Moscow.