ABC News' Kirit Radia reports: Defense Secretary Robert Gates said that US troops may pick up the pace of withdrawing from Iraq this year. Gates said yesterday he has been "heartened" by progress since US troops pulled out of Iraqi cities a month ago, allowing Iraqi forces to assume more responsibility for security. Gates made his comments on his plane on the way back to Washington from a surprise visit to Iraq after a swing through the Middle East. Gates said of the pace of US troop withdrawal: "I don't think there is anything in the cards for a slow down, I think there is some chance for a modest acceleration. But because of the way General Odierno sees things going that remains to be seen." How many troops is he talking about? Perhaps the withdrawal of an additional Brigade Combat Team before Iraqi elections slated for early next year. The original plan was to reduce the number from 14 BCTs to 12 by the end of this year, Gates said. A troop agreement signed with Iraq in the waning days of the Bush administration calls for US troops to leave the country by the end of 2011. Gates said Odierno is "looking at all the possibilities and he is very encouraged by things so far." But Gates cautioned this is contingent on the security situation in the country remaining calm. "I don't want to put the general in a corner, it really depends on circumstances and it may or may not happen. I mention it because it is an indicator that things are going pretty well post June 30th," he said, referring to the date when US troops pulled out of Iraqi cities, a move seen as a major test of Iraqi forces' ability to maintain security for themselves. While in Iraq Gates warned that sectarian tensions and clashes over oil in the country's northern Kurdish regions could be sources of instability going forward. After this week US troops will be the only foreign forces remaining in the 'Multi-National Force.' British forces will soon pullout and their residual training force has to withdraw to Kuwait temporarily because the Iraqi parliament failed to pass an authorization for their presence before leaving on recess. The other members have already left or will do so before the end of the month.