PRECIOUS-Gold firms on Brexit jitters but trade optimism caps gains

* UK PM Boris Johnson faces votes at 1800 GMT
* Gold could break $1,479/oz support, fall to $1,456 -
technicals
* Silver gains for fifth consecutive session

(Updates prices)
By Eileen Soreng
Oct 22 (Reuters) - Gold prices inched higher on Tuesday
ahead of a crucial vote by British lawmakers on the Brexit
withdrawal agreement, although prospects for a U.S.-China trade
deal limited bullion's gains.
Spot gold XAU= was up 0.2% at $1,487.63 per ounce as of
1042 GMT, having hit a roughly one-week low of $1,480.44. U.S.
gold futures GCcv1 were also up 0.2%, at $1,490.70.
"There is an uncertainty about Brexit and some people
realise that there still are roadblocks ahead," Quantitative
Commodity Research analyst Peter Fertig said.
"We have a rebound in government bond prices, including in
Germany and Italy, which is pointing to a flight back into safe
havens," Fertig said, noting declining yields are supportive for
gold.
Euro zone government bonds edged down before a vote in the
British parliament crucial to determining whether the United
Kingdom can leave the European Union in an orderly way at the
end of the month. Prime Minister Boris Johnson faces two pivotal votes in
parliament on Tuesday that will decide whether he can deliver on
his pledge to lead Britain out of the EU in nine days' time.
Lawmakers vote at around 1800 GMT on the 115-page Withdrawal
Agreement Bill and then on the government's extremely tight
timetable for approving the legislation. Capping bullion's gains was optimism induced by talk of
progress in China-U.S. trade negotiations that propped up
sentiment for riskier assets. MKTS/GLOB
"The precious metal is waiting for the next big theme or
market-moving event that will influence global sentiment and
risk appetite," FXTM analyst Lukman Otunuga said in a note.
"Until something fresh is brought into the picture, gold is
positioned to trade within a modest range in the short to medium
term," Otunuga added.
China and the United States have achieved some progress in
their trade talks, Chinese Vice Foreign Minister Le Yucheng said
on Tuesday. Those comments came a day after U.S. President Donald Trump
spoke of optimism about a deal, while White House adviser Larry
Kudlow said tariffs on Chinese goods scheduled for December
could be withdrawn if talks went well. Spot gold is poised to break support at $1,479 per ounce and
fall towards the next support at $1,456, Reuters technical
analyst Wang Tao said. Silver XAG= rose 0.4% to $17.63 an ounce, gaining for a
fifth straight session. Platinum XPT= was up 0.2% at $889.77
and palladium XPD= was 0.1% higher at $1,759.47 an ounce.