The United States and Qatar signed an agreement aimed at combating the financing of terrorism, as U.S. Secretary of State Rex Tillerson visited Doha to try to end a month-long rift between western-allied Arab states.

Tillerson said the agreement signed with his Qatari counterpart, Sheikh Mohammed Bin Abdulrahman Al-Thani, had been under discussion for months.

Saudi Arabia, Bahrain, the United Arab Emirates and Egypt imposed sanctions on Qatar last month, accusing it of financing extremist groups and allying with the gulf Arab states’ arch-foe Iran, something Doha denies.

Sheikh Mohammed said the agreement was not linked to the crisis with the four Arab countries, which the United States fears could impact its military and counter-terrorism operations and increase Iran’s influence in the region.

The Qatari Minister also said his country had not broken any promise under the Riyadh agreement, a previously secret accord between Riyadh and Doha.

The four Arab states say Qatar had pledged to desist from interfering in its neighbors politics in the 2013 agreement.