The Obama administration, stung by reversals in Ukraine and Syria, appears to have decided to expand its covert program of training and assistance for the Syrian opposition, deepening U.S. involvement in that brutal and stalemated civil war.

This stepped-up assistance program is likely to be discussed during talks Friday between President Obama and Saudi King Abdullah. U.S. endorsement of the program would tighten America’s links with Saudi Arabia after a period of noisy disagreement about Syria policy. But it also would complicate already tense relations with Russia and Iran, the two key backers of Syrian President Bashar al-Assad.

Obama appears more comfortable with a covert approach than with direct military intervention, as in Iraq and Afghanistan. Another selling point is that the enhanced aid program would have a counterterrorism focus. The United States would help train Free Syrian Army fighters to combat al-Qaeda extremists, even as the rebels launch guerrilla attacks against Assad’s army.

Critics argue that an expanded training and assistance program, first recommended by Obama’s top advisers in mid-2012, is long overdue — and that delays have allowed extremists and Assad’s forces to brutalize Syria. But Obama has been cautious about descending what he sees as a slippery slope. So far, despite pledges of support for the opposition, he has authorized only a limited program of covert training and mostly nonlethal assistance. He also recognizes the checkered history of such covert efforts, from the Bay of Pigs in Cuba to Nicaragua.

Details of the plan were still being debated Thursday, but its likely outlines were described by knowledgeable officials:

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●Syrian opposition forces would be trained in camps in Jordan, northern Saudi Arabia and Qatar. The number of Syrian opposition fighters who would receive training would roughly double, to about 600 per month.

●The CIA would oversee training, expanding the program that it currently manages. The administration is still discussing whether U.S. Special Operations forces and other military personnel should play a role. Syrian rebels have argued that Special Operations trainers would provide better help, without the CIA’s political baggage.

●The rebels have been pleading for two years for anti-aircraft missiles to stop Assad’s air force, but Saudi Arabia wants U.S. permission before delivering them. To reassure the United States, the opposition has proposed tight controls on these weapons, known as “MANPADS.” Only five missile launchers would initially be furnished. Each use of them is to be videoed, and each would be fitted with a tracking device and a remote shutdown mechanism. As of late Thursday, the administration still appeared to be weighing the issue.

●Vetting of opposition forces would continue during and after the training. Recruits with extremist links supposedly would be weeded out as trainers learned their backgrounds. Saudi Arabia has agreed to exclude any fighters who have worked with three jihadist groups: Ahrar al-Sham, Jabhat al-Nusra, and the Islamic State of Iraq and Syria.

●The sometimes fractious “friends” of the Syrian opposition would, in theory, be united behind this program. Qatar, which in the past funneled aid to organizations known as the Islamic Front, support that later made its way to al-Qaeda extremists, has agreed to halt this assistance.

Qatar has also offered to finance the combined program in its first year, which could run to hundreds of millions of dollars. Saudi Arabia, a sharp critic of Qatar, may resist this donation. It is unclear what role would be played by Turkey, which has been accused of allowing Muslim extremists to operate across its border with Syria.

●To stabilize what is today a badly fragmented Syria, the program would provide assistance for local councils and police in areas that have been cleared of Assad’s forces. The opposition has also requested specialized training to maintain border security. Finally, the program may seek to establish corridors for delivery of humanitarian assistance, though it is unclear how aggressively the United States and its allies would be prepared to protect these humanitarian zones.

The expanded program would “send a clear message to the Assad regime that there is no military solution to the struggle,” according to a March memo to the White House from the opposition. Assad “has no incentive to talk” now, the memo argued, because he thinks he is winning.

The rationale, bluntly stated, is that to reach an eventual diplomatic settlement in Syria, it is necessary now to escalate the conflict militarily. This has been a hard pill for Obama to swallow, but prodded by the Saudis, he seems to have reached that point.

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