China accused Taiwan’s ruling party of damaging the chances of peaceful unification, as authorities in Beijing attempted to keep the pressure on Taipei a week after U.S. House Speaker Nancy Pelosi’s visit.

The Democratic Progressive Party helmed by President Tsai Ing-wen must change course to reduce tensions, the Taiwan Affairs Office in Beijing said, in its first white paper published since Chinese President Xi Jinping took power. The report said DPP leaders deepened the dispute by refusing to accept that both sides belong to "one China.”

China won’t rule out the use force to unify the two sides, the paper said, reaffirming the Communist Party’s long-stated position that it would reserve all necessary options.