The Pentagon announced last week that some 2,000 U.S. troops are currently deployed in Syria, raising the official count almost four times the previous figure of 500.

The U.S. increase in troops comes as Russian President Vladimir Putin announced a withdrawal of Russian troops from Syria Monday, after a declaration of victory over the Islamic State in Syria.

The Pentagon's announcement came a month after Army Maj. Gen. James B. Jarrard, told reporters at a news conference there were about 4,000 U.S. troops in Syria. Jarrard's statement was immediately revised by the Pentagon to 500.

The latest announcement by Army Col. Rob Manning, a Pentagon spokesman, was said to be part of a new push by U.S. Defense Secretary and former general Jim Mattis to be transparent about how many troops are deployed in combat zones.

“That’s where we are now,” Manning said. “If a major shift occurs, then we’ll come back out with a new, official number.”

The latest Pentagon announcement echoes a November report from the Defense Department showing U.S. troops in the Middle East have increased 33% in the last four months and currently stand at 1,723 in Syria - up from 1,251 in June.

Mattis himself announced at the beginning of the month that as offensive operations against Islamic State in Syria entered their final stages, he expected the focus to move towards holding territory instead of arming Syrian Kurdish fighters.

The Syrian Kurdish YPG spearheads the Syrian Democratic Forces (SDF), an alliance of Kurdish and Arab militias fighting Islamic State with the help of a U.S.-led coalition.

The United States expects to recover heavy weapons and larger vehicles from the YPG, but lighter weapons are unlikely to be completely recovered, U.S. officials have said.

Earlier this week, the U.S.-led coalition fighting Islamic State said more than 400 U.S. Marines and their artillery would be leaving Syria after helping to capture the city of Raqqa from Islamic State.

Mattis said that was part of the United States changing the composition of its forces to support diplomats to bring an end to the war.

"The troops are changing their stance...that includes with our allies who are now changing their stance as they come to the limits of where they are going," Mattis said.