President Barack Obama made separate phone calls to Palestinian President Mahmoud Abbas and Israeli Prime Minister Benjamin Netanyahu on Thursday, a senior White House official told NBC News — a move that underscores the high stakes in the two sides' just-begun peace talks. The phone calls come days after Israeli and Palestinian negotiators met in Washington with Secretary of State John Kerry. In his phone calls to the two sides' leaders Thursday, Obama stressed his support for the peace process and urged both sides to maintain momentum to achieve results. The two sides are expected to negotiate for about nine months in hopes of reaching a new peace deal, three years after the talks last collapsed.