It has also led U.S. Defense Secretary Chuck Hagel to postpone an ICBM test launch scheduled for Tuesday to avoid a" misperception or manipulation"of the test by North Korea.
On Sunday, Col. Amy Hannah, a U.S. Forces Korea spokesperson, said that Gen. James Thurman, the commander of U.S. and U.N. forces in South Korea, would not be traveling to Washington this week for previously scheduled congressional budget hearings.
"Given the current situation General Thurman will remain in Seoul next week as a prudent measure. He has asked the Senate Armed Services Committee," said the statement.
The statement says that Thurman had asked three congressional committees to " to excuse his absence until he can testify at a later date. He looks forward to appearing before the committee at the earliest possible date."
Earlier on Sunday it was announced that South Korea's top military officer was rescheduling a planned visit to Washington because he could not be away while North Korea was making bellicose threats.
South Korean Joint Chiefs of Staff Chairman Gen. Jung Seung-jo was to have visited the Pentagon on April 16 to meet with his American counterpart, Gen. Martin Dempsey, the chairman of the Joint Chiefs of Staff, for regular consultative meetings.
The meeting in April had been scheduled during their previous meeting in October.
Both the U.S. and South Korea believe that North Korea may be planning to soon test launch as many as two Musudan medium-range missiles that were spotted earlier last week moving by train to its east coast. The missiles' exact location has not been pinpointed since then.
On Saturday, Pentagon officials confirmed that Defense Secretary Hagel had delayed a Minuteman 3 missile test scheduled for Tuesday at Vandenberg AFB in California "to avoid misperception or manipulation" by North Korea. Minuteman 3's are intercontinental ballistic missiles (ICBM's).
The official said the test has been long planned "and thus unconnected from the recent tensions with North Korea."
"We recognized that an ICBM test at this time might be misconstrued by some as suggesting that we were intending to exacerbate the current crisis with North Korea," the official said. "We wanted to avoid that misperception or manipulation.
According to the official, Hagel made his decision Friday night.
The test was for the Air Force and not part of the Missile Defense Agency's program to test missile interceptors as part of the missile defense program designed to counter a North Korean missile threat to the U.S.
MDA routinely conducts tests of the interceptor missiles and uses Minuteman 3-s for targeting purposes.
The test that had been planned for Tuesday was part of a long-scheduled series of launches for the Air Force's Global Strike Command to test the effectiveness of the Minuteman 3 fleet.
The U.S. has 450 of the missiles in its arsenal that are equipped to carry nuclear warheads.