Hong Kong (CNN Business) Asian markets mostly fell slightly on Monday, pulling back a bit from last week's gains.

Hang Seng Index HSI Nikkei 225 N225 Kospi KOSPI Hong Kong'sretreated 0.3%, while Japan'sand South Korea'sboth moved marginally lower.

Shanghai Composite Index SHCOMP China'sbriefly lost 0.3%, but later erased the losses and was last trading flat, but in positive territory.

The slump came after all four indexes jumped Friday on news that the United States and China had reached a "phase one" trade deal that rolled back some tariffs and led Washington to cancel another round of duties scheduled to take effect Sunday.

Beijing on Sunday also called off additional tariffs set to kick in on US goods.

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