Supermarkets rallied on the back of Morrison's strong Christmas trading, helping to push the FTSE 100 0.3% higher to 7,724 around midday.
Morrisons (MRW) reported a 2.8% jump in like-for-like sales excluding fuel in the 10 weeks to 7 January, causing the shares to rise 1.9% to 231.2p.
Investors had a positive read across to other companies, including Marks & Spencer (MKS), which topped the blue-chip leader board with a 3.2% rise to 320.8p.
Supermarket Sainsbury's (SBRY) advanced 2% to 245.7p.
Brent crude was unmoved at $67.86 per barrel.
Wall Street continued its strong performance overnight with the exception of the Dow Jones, which was flat at 25,283.
MID AND LARGE CAP RISERS AND FALLERS
Housebuilder Persimmon (PSN) upgraded its annual profit guidance after increasing sales by 9%. Its shares retreated 1.1% to £27.17 as investors focused on warning of potential risks from Brexit.
Dechra Pharmaceuticals (DPH) received a 2.3% boost to £20.52 thanks to a strong trading update, including 20% sales growth in North America and a 'modestly favourable' effect from US tax reform.
Specialist building products distributor SIG (SHI) reported its previously overstated its cash position, triggering a 3.2% decline to 167.7p.
Student accommodation specialist Unite (UTG) achieved occupancy levels of 99% for the current academic year, although this failed to boost the shares at 813p.
Insurer Hastings (HSTG) was flat at 311.6p following its chairman Mike Fairey standing down. Chief executive Gary Hoffman was flagged as his replacement.
SMALL CAP RISERS AND FALLERS
Carr's (CARR) pleased the market as trading in its agriculture and engineering division were significantly ahead of the prior year. The company said positive farmer sentiment in the UK and improved manufacturing activity were behind the encouraging results. Shares in Carr's rallied 16.1% to 144p.
There was also strong trading at Topps Tiles (TPT) over the Christmas period, up 7.5% at 85.9p. The UK's largest tile specialist reported a 3.4% increase in like-for-like sales in the 13 weeks to 30 December.
Shares in promotional products marketer 4imprint (FOUR) soared 8.7% to £20.38 after revealing that the US tax reform would result in a beneficial impact on earnings and cash generation.
Embattled Carillion (CLLN) sank 11.5% to 21.1p following a rally on Monday after investors were excited by the possibility the contractor would strike a deal with its lenders, which did not materialise.
Recruiter Robert Walters (RWA) dipped 1.9% to 645.2p despite delivering a 19% rise in gross profit of £90.5m in the quarter to 31 December 2017.