LONDON (Reuters) - Britain's biggest supermarket group Tesco TSCO.L was the best performer over Christmas, Kantar Worldpanel said on Tuesday, with a 3.1 percent rise in sales in the past 12 weeks beating its "big four" rivals Sainsbury's, Asda and Morrisons.

FILE PHOTO: A woman walks past a Tesco supermarket in central London, December 9, 2014. REUTERS/Toby Melville/File Photo

Asda, owned by Walmart WMT.N, increased sales by 2.2 percent in the period to Dec. 31, while 2.1 percent more came through the tills at Morrisons MRW.L and Sainsbury's SBRY.L was up 2.0 percent, the research group said.

But growth at Aldi [ALDEI.UL] and Lidl continued to outpace the four, with both discounters seeing sales rise by 16.8 percent.

“Overall supermarket sales increased in value by 3.8 percent, with an additional 1 billion pounds ($1.35 billion)ringing through the tills compared to the same festive period last year,” said Fraser McKevitt, Kantar Worldpanel’s head of retail and consumer insight.

“Shoppers parted with 747 million pounds on Dec. 22 alone, making the Friday before Christmas the busiest shopping day ever recorded.”

Morrisons beat forecasts on Tuesday for underlying Christmas sales, as premium products, online sales and competitive prices lured more shoppers into the fourth biggest supermarket group.

Morrisons was the first of the big four to report on Christmas trade. Sainsbury’s, the No. 2, reports on Wednesday and Tesco updates on Thursday.

Rival market researcher Nielsen also named Tesco the best Christmas performer among the major grocers on Tuesday, although Asda outpaced it in the shorter December period.

Grocery inflation stood at 3.7 percent for the period, Kantar said.

($1 = 0.7394 pounds)