U.S. President Barak Obama praised US-Qatari security cooperation to fight the Islamic State (IS) militants, during Qatari Emir, Sheikh Tamim bin Hamad Al Thani's first White House visit on Tuesday. "Qatar is a strong partner in our coalition to degrade and ultimately defeat IS," said Obama. For his part, the Emir praised the solid bilateral relationship between the two countries, asserting that his country seeks to advance the Middle East peace process. "We have to find a solution for Palestine. And I'm happy to learn, to hear from you Mr President, that you're committed," Qatar's Emir said. The visit came following the US congress warning letter to President Obama accusing Qatar - one of America's most important military allies in the Middle East - of funding and providing weapons to IS militants, pointing out that U.S. has been sending billions of dollars and weapons to Qatar to keep it as a regional strategic ally. "The Qatari government turns a blind eye to terrorist fundraising for Al Qaeda and the Islamic State by U.S.-designated persons within its borders," the letter read. Last year, the US Treasury Department announced that an unnamed Qatari businessman had given $2 million to an IS leader, and that virtually no prosecutions had taken place for violations of financial counter-terrorism laws. A number of Gulf countries have even accused Qatar of supporting terrorism, but the Qatari Emir rejected such allegations, saying "what is happening in Iraq and Syria is extremism and such organizations are partly financed from abroad, but Qatar has never supported and will never support terrorist organizations".