WASHINGTON (AFP) - US and Chinese officials are working on a deal to postpone a round of tariffs set to hit Chinese imports in five days, according to a media report on Tuesday (Dec 10).

Delaying the new duties, which cover about US$160 billion (S$220 billion) in imports, including consumer favourites like mobile phones, could help reassure markets the two sides are making progress towards ending their trade war.

Officials on both sides say they now expect to continue talking past Dec 15, when the tariffs are due to kick in, according to The Wall Street Journal.

The report helped move Wall Street futures into positive territory.

US officials have reiterated that any final decision by the American camp belongs to President Donald Trump.

At a Wall Street Journal conference on Tuesday, top White House economic aide Larry Kudlow maintained that "those tariffs are still on the table," the newspaper reported.

Kudlow had said Friday a deal was "still close."

For two months, the two sides have struggled to finalise a partial deal that Trump announced in October.

Statements by US officials have run hot and cold in recent days, with markets swooning last week after Trump said a deal could wait until after next year's elections.

But Larry Kudlow, a top White House economic aide, said Friday a deal was "still close."

Trump launched his trade war in March 2018, demanding that China end practices widely seen as unfair - such as forced technology transfers from US firms, and massive subsidies given to Chinese firms.

But observers say Beijing is highly unlikely to make profound changes to the structure of its economy sought by Washington, which could politically undermine the Communist Party.

Trump has also sought pledges from Beijing to make enormous purchases of US farm exports that experts say may exceed demand in China.

Should the Dec 15 tariffs take effect, virtually all the merchandise the United States imports annually from China will be covered by punitive tariffs.