U.S. investigators believe Russian hackers breached Qatar's state news agency and planted a fake news report that contributed to a crisis among the US' closest Gulf allies, according to USA officials briefed on the investigation.
Qatar has found itself increasing isolated since Monday, when neighbors Saudi Arabia, Egypt, Bahrain and the United Arab Emirates (UAE) declared that they were cutting off all air, sea and land transport links to the tiny Gulf nation.
Al-Shamsi said these new measures were in response to Qatar's "hostile and irresponsible" policies against the UAE and against the "other Gulf and Arab brotherly states".
Two days earlier, Bahrain's Civil Aviation Authority revoked Qatar Airways' operating license, giving all the carrier's offices in Bahrain 48 hours to close their doors.
U.S. President Donald Trump took sides in the rift on Tuesday, praising the actions against Qatar, but later spoke by phone with Saudi King Salman and stressed the need for Gulf unity.
Defense Secretary James Mattis also spoke to his counterpart in Qatar to express U.S. commitment to security.
USA military officials, also speaking anonymously to discuss political issues, said the Al Udeid airbase in Qatar is vital to American air support against Iranian paramilitaries and Iranian-backed forces on the side of Syrian President Bashar al-Assad in Syria's civil war.
Putin had a telephone conversation with the emir of Qatar Tuesday, urging dialogue. "The United States appreciates Qatar's role as a coalition partner in the fight against ISIL".
But Qatari Foreign Minister Sheikh Mohammed Bin Abdul Rahman al-Than said there was "no evidence that the Qatar government is supporting radical Islamists".
During the phone call, Mr. Trump underscored that a united Gulf Cooperation Council is critical to defeating terrorism and promoting regional stability, the White House said. This led to panic in Qatar as citizens rushed to stockpile move.
Ankara officials have said Turkey's parliament will fast-track a draft bill allowing its troops to be deployed to a military base in Qatar.
Adel al-Jubeir also addressed claims Qatar had drafted in the FBI to investigate how its state-run news agency was "hacked" in an incident that first rocked diplomatic relations.
"We are courageous enough to sit and talk about it to change the course", Al-Thani said.
The four governments also closed their airspaces to all Qatari flights and banned Qatar-based news giant Al Jazeera.
"We see Qatar as a brother state, as a partner", he told a joint press conference with German counterpart Sigmar Gabriel, according to the German simultaneous translation.