White House economic adviser Larry Kudlow said the call "went well" and the two sides were talking about a face-to-face meeting, but he warned there was no magic way to reach what has so far been an elusive deal.
London nickel rose as much as 2.1% to $12,970 a tonne, its highest since April 17, while Shanghai nickel jumped to 103,160 yuan ($14,984.60) a tonne, a three-month high, before easing to end at 102,010 yuan a tonne.
FUNDAMENTALS
* LEAD PRICES: Shanghai lead hit a two-month high at 16,450 yuan a tonne but eased later in the session and closed at 15,995 yuan a tonne, while London lead hovered around a one-week high, trading up 0.8% at 0709 GMT.
* LEAD: The discount between LME cash and three month contract <CMPB0-3> contracted to $2.5 a tonne, from around $15 a week earlier, indicating a tighter market. Lead stockpiles <MPBSTX-TOTAL> have been around a 10-year low level.
* NYRSTAR: Metals and mining company Nyrstar said it was extending force majeure at its Port Pirie lead and zinc smelter in Australia until the last week of July, from the second week of this month as previously planned.
* ZINC: London zinc rebounded 1.4% from a 10-month-low, but Shanghai zinc dipped 0.1% at the close, following LME zinc's decline in the previous session.
* "Our physical balance measure suggests the ex-China market has moved into surplus. China still looks tight. We expect any ex-China excess will flow East, putting in near term support for LME but loosening the China balance," Citi said in a note.
* SCRAP: China issued import quotas for 124,450 tonnes of high-grade copper scrap and 306,930 tonnes of aluminium scrap, on top of its initial quotas for around 240,000 tonnes of copper scrap and about 54,000 tonnes of aluminium scrap.
* CHINA: China's producer prices flatlined in June on lower oil prices and weak global demand, fuelling concerns that a slowdown in manufacturing from a bruising trade war will further drag on growth in the world's second-biggest economy.
* PRICES: London copper rose 0.7% and aluminium advanced 0.2%. In Shanghai, copper fell 0.5%, but aluminium advanced 0.4% and tin was up 0.4%.
* BOSNIA ALUMINIUM: Bosnia's sole aluminium smelter and one of the country's biggest exporters was shut down on Wednesday over a huge debt it had incurred because of high electricity and alumina prices.
* COPPER: Southern Copper Corp said on Tuesday it received a construction permit for its long-delayed $1.4 billion Tia Maria copper mine project in Peru, but said work would not begin until it gains more support from local residents.