WASHINGTON (REUTERS) - The United States said on Wednesday that it is concerned about the increase in tensions between Taiwan and the Philippines over the killing of a fisherman from Taiwan last week and urged them to work their through their differences as quickly as possible.

"We urged the Philippines and Taiwan to take all appropriate measures to clarify disagreements and prevent recurrence of such tragic events," State Department spokesman Patrick Ventrell said.

"We continue to urge both parties to ensure maritime safety and refrain from actions that could further escalate tensions in the region and undermine prospects for a rapid and effective resolution of differences," he added.

Taiwan imposed sanctions against the Philippines on Wednesday rejecting as unacceptable a Philippine apology for the killing of the fisherman last week.