During a February 5 hearing held by the Senate Armed Services Committee, Gen. Joseph Votel explained, "I was not aware of the specific announcement".
Last month Israel admitted it had attacked Iranian military targets in Syria in what was one of the first times the state has taken responsibility for any strike on Syria.
The US president had long questioned America's multiple and seemingly interminable wars, but his withdrawal order came as a shock to Washington, upending years of doctrine in Syria.
It took more than 60 minutes for Donald Trump to mention the Middle East in his State of the Union speech, but when he did, the USA president defended his decision to pull American troops out of Syria, despite opposition among the nation's top military and intelligence brass and from the president's own political party.
That decision prompted the resignations of Secretary of Defense James Mattis and the Special Presidential Envoy to the Counter-ISIS campaign Brett McGurk.
Trump's latest remarks had made passing such a law "a national duty", he said.
He added that territory under Isis control had been reduced to less than 20 sq miles (5,180 hectares) and would be recaptured by US-backed forces prior to the U.S. withdrawal, which he said would be carried out in a "deliberate and coordinated manner".
Russian Federation to design new intermediate range missiles in 2 years
The US in December gave Moscow a 60-day deadline to dismantle missiles it said breached the agreement. He said the military must reconfigure the existing defence budget to find money for the new weapons.
WhatsApp for iPhone Gets Face ID, Touch ID Biometric Authentication
Messages will still be partially visible via notifications, and they can still be quick-replied to. Some manufacturers, like Samsung and Huawei, bake similar features right into their Android skins.
LeBron James to Make Return Against Clippers
Lou Williams scored 24 points off the bench to lead the Clippers, who had won 22 of their previous 25 matchups against the Lakers. The current injury stint has been the longest James' 16-year National Basketball Association career.
"The drawdown of troops is essentially a tactical change - it is not a change in the mission", said Pompeo. "In Afghanistan and Iraq, almost 7,000 American heroes have given their lives", said Trump, while explaining why he wants to bring his troops home.
Interviewer Jeff Glor interrupted Pence to note that Trump has claimed that ISIS will be totally defeated in a matter of days. "We might as well keep it".
"We do not know whether we will achieve an agreement - but we do know that after two decades of war, the hour has come to at least try for peace", he said. "It is time", Trump said. And the other side would like to do the same thing. "He has also served as an anti-terrorism expert, and a Jewish community leader who has played a prominent role in defending the safety of the Jewish people at home and overseas", Pompeo said on Tuesday.
"We have to protect Israel", he told CBS News's Margaret Brennan on Sunday.
Pompeo said, "To that end, we ask that our coalition partners seriously and rapidly consider requests that will enable our efforts to continue". He also reaffirmed his determination to pull out roughly 2,000 USA troops from Syria. And Votel replied, "We were not". And he meant it and it's about week since they really got going and they'll be informing us very soon officially that it's 100 percent'.
His comments come amid renewed efforts in both the House and Senate to block United States support to the Saudi-led coalition.
"We are still ready to accept America's... repentance despite the fact that for years it has done injustice to us", he told foreign diplomats in Tehran during a ceremony to mark the 40th anniversary of Iran's Islamic Revolution.
A Defense Department Inspector General report released on Monday concluded that Iraq's failure to seat new heads of the Defense and Interior ministries has hampered the rebuilding of Baghdad's military.