More than 20 international aid organizations have sharply criticized the United Nations Security Council, saying it has failed to implement three resolutions passed last year seeking to boost humanitarian assistance to Syrian civilians.

The 21 aid groups say the resolutions have been "ignored or undermined by the parties to the conflict, other U.N. member states, and even by members of the UNSC itself."

They said in a report released Thursday that despite the resolutions violence in Syria has intensified, aid access has decreased and humanitarian assistance remains "chronically underfunded."

The aid groups, including the International Rescue Committee, the Norwegian Refugee Council and Handicap International, call on U.N. members to ensure the resolutions are fully implemented.