The FTSE 100 added 0.3% and the mid-cap FTSE 250  was up 0.2% by 0749 GMT.

The South China Morning Post (SCMP), citing sources, said Washington and Beijing had agreed to a truce before leaders of the two nations meet at the G20 summit, putting the next round of U.S. tariffs on more Chinese goods on hold.

That helped shares of HSBC and Prudential boost the blue-chip index, while miners such as Rio Tinto  and BHP also provided support as copper prices strengthened.

Thursday's gains put the FTSE 100, which had already rallied this month on bets that the U.S. Federal Reserve would cut interest rates, on course for its biggest monthly gain since April 2018.

"We can now expect an awful lot of newsflow on trade and tariffs over the next two days, so it's wise to be cautious about reading too much into statements," Markets.com analyst Neil Wilson said.

Home improvement retailer Kingfisher rose 3.5% and was on track for its best day in more than four months after it named Carrefour's Thierry Garnier as its new chief executive.

BAT was the most notable blue-chip stock in the red, giving up 1.3% on a combination of a modest rise in the pound and ex-dividend trading.

Engineering firm Senior tumbled almost 11% on the mid-cap index and was on course for its worst day in more than 2-1/2 years. Traders cited the fall to Barclays downgrading its rating on the stock to 'equal-weight' from 'overweight'.

Serco climbed 6% to a more than two-year high, however, after a recent run of contract wins helped the outsourcer nudge its annual revenue target higher.

Shares of Pendragon, hammered earlier this month after a profit warning, slid 4% after the car dealership said its chief executive would step down because of a "difference in priorities", delaying its strategic review.

"We maintain our view that Pendragon's problems are multiple and deep-rooted and that any management team will face an uphill challenge in the current trading environment," Liberum analysts wrote.