Pompeo overruled the department's specialists, who were concerned about the rising civilian death toll in Yemen, the Wall Street Journal reported, citing a classified State Department memo and people familiar with the debate.
The article estimated that the value of the future weapons sales was at least $2 billion.
A recent UN report found that the Saudi-led coalition airstrikes were responsible for most of more than 16,000 civilians killed or injured in Yemen over the past three years.
Saudi airstrikes have hit open-air markets, funerals, a wedding and most recently, a school bus in killing more than 40 Yemeni students on a field trip in August.
For weapons sales to continue, the State Department is required to certify every six months that the Saudi-led coalition is taking steps to minimize civilian casualties.
State Department specialists argued that Pompeo could decline the certification but still allow weapons sales to continue by invoking a US national security exemption, according to the Journal.