SHARECOMMENTMORE

WASHINGTON (AP) - Lawmakers in both parties say President Barack Obama's warning against Syria's use of nerve gas may now force the administration to act.

The White House acknowledged Thursday that the Syrian government has twice used chemical weapons in the two-year civil war.

Lawmakers emerging from a closed-door briefing with Secretary of State John Kerry said Friday that failure to respond would have widespread implications, potentially emboldening rivals like North Korea and Iran.

Yet lawmakers were cautious about what the next steps should be, reflecting wariness about aggressive U.S. military involvement in a Mideast war.

Republican Rep. Hal Rogers of Kentucky says simply that Syria is "such a muddled picture."