Debbie Stothard, deputy secretary-general of the International Federation for Human Rights, said members of the international community are being seduced by "empty promises" made by Myanmar President Thein Sein.
"Instead of making sweetheart deals in favor of trade and investment, the international community must push for the immediate and unconditional release of all political prisoners and for genuine legislative reform in [Myanmar]," she said in a statement Friday.
Several nations have relaxed sanctions on Myanmar, the country formerly known as Burma, in response to political reforms that began with democratic elections in 2010. Human rights groups argue it was those sanctions that encouraged many of the reforms in the first place.
Stothard's group said Myanmar's president released more than 200 political prisoners from custody last year although nearly 40 others were still in jail at the start of 2014.
Rupert Colville, a spokesman for the U.N. High Commissioner for Human Rights, said Friday he welcomed a Jan. 2 decision from Myanmar's president to commute all death sentences to life terms.
Myanmar hasn't carried out a death sentence since 1989, he said in a statement.