[cnn-photo-caption image= http://i2.cdn.turner.com/cnn/2010/images/01/04/art.hrc0104.gi.jpg caption="Secretary Clinton held a press conference at the State Department Monday in Washington."]
Washington (CNN) - Secretary of State Hillary Clinton on Monday called the situation in Yemen a possible threat to regional and global security.
"We see global implications from the war in Yemen and the ongoing efforts by al Qaeda in Yemen to use it as a base for terrorist attacks far beyond the region," Clinton said after a meeting with the prime minister of Qatar.
Clinton's comments came as the U.S. Embassy in Yemen remained closed a second day due to what Clinton called "ongoing threats by al Qaeda in the Arabian Peninsula."
The threats "certainly pre-date this holiday season, and they are aimed at American interests in Yemen," Clinton said, adding a decision on reopening the embassy will be made "when the security conditions permit."
Great Britain also closed its embassy in Yemen, while France, Spain, Japan and Germany made changes to enhance embassy security.
Senior administration officials told CNN on Monday that the U.S. Embassy was closed after a "specific and credible" threat.
One official said the government had information that eight al Qaeda operatives in Yemen were planning an attack on the embassy. Three were killed and a fourth, wearing a suicide vest, was wounded in a recent air strike by Yemeni authorities, but the other four were believed to still be at large, prompting the embassy's closing, the official said.
Clinton commended Yemen for taking action against al Qaeda networks and added: "We are reiterating our commitment to assist in those efforts."
Last year, Yemen received U.S. development and security assistance totaling $40.3 million. For the current fiscal year, the appropriation for total direct assistance to Yemen is $52.5 million.
In addition, Yemen could receive additional U.S. funding dedicated to counterterrorism efforts.
On another issue, Clinton said Monday that the State Department "fully complied" with existing requirements for screening potential terror threats in the failed Christmas Day bomb attempt on a U.S. airliner.
The suspect, Umar Farouk AbdulMutallab, had a multiple-entry U.S. visa. His father, a leading banker in Nigeria, warned U.S. authorities before the attack that his son might be involved with Islamic extremists, but the information failed to prompt a response such as canceling the visa.
Clinton acknowledged her team was examining whether its procedures should change as part of a government-wide review ordered by President Barack Obama.