WASHINGTON - President Barack Obama says a vaccine for the Zika virus could be developed in "fairly short order" if Congress acts quickly to pass a bill to prevent the spread of the disease.

Obama says researchers are beginning to develop and test a vaccine for the mosquito-borne virus. He says that if the effort is well funded he's "fairly confident" an effective vaccine could be developed before the virus spreads to the continental U.S.

Obama made the remarks Friday after being briefed by top health officials at the White House.

The president is trying to pressure Congress to pass a Zika-prevention bill that has been stalled for weeks. He criticized lawmakers for "playing politics" with public health. He says lawmakers should not take their summer recess before passing a bill.