LONDON (Reuters) - Britain's top share index ended slightly lower on Thursday, with companies such as National Grid (>> National Grid plc) and Marks & Spencer (>> Marks and Spencer Group Plc) falling after trading without the attraction of their latest dividend payouts and energy firms tracking weaker oil prices.

The blue-chip FTSE 100 index <.FTSE> finished 0.1 percent at 6,185.61 points, dragged down by a 4.6 percent and 2.6 percent fall in National Grid and Marks & Spencer respectively.

The FTSE is down nearly 1 percent so far in 2016, and some 13 percent below a record high reached in April 2015, with concerns over a slowdown in China - the world's second-biggest economy - having hit global stock markets.

The UK energy index <.FTNMX0530> fell 0.1 percent after oil prices dropped more than 1 percent as the Organization of the Petroleum Exporting Countries ended its meeting without any apparent change in its crude production policy. [O/R]

"There were high expectations that something positive was going to come out of the OPEC meeting and it turned out that there was no agreement again. As a result, energy stocks, which traded higher earlier, surrendered gains," Jawaid Afsar, senior trader at Securequity said.

"With crude oil trading towards the $50 mark, there is little upside potential in the short term for energy stocks."

Some traders said they would use any move higher on the FTSE to sell out and cash in profits, given uncertainty over the Brexit vote this month on Britain's membership of the European Union.

"I'd be looking to sell the rallies here," said Dafydd Davies, partner at Charles Hanover Investments.

Concern about the June 23 referendum on Britain's EU membership also led to British construction orders falling last month for the first time in more than three years.

Shares in heating and plumbing supplies group Wolseley (>> Wolseley plc) fell 1.1 percent, following broker downgrades on the stock, while the FTSE 350 Construction & Building Materials Index <.FTNMX2350> fell 0.1 percent.

The UK market showed little reaction to the European Central Bank's move to keep interest rates on hold, as expected. The ECB raised growth and inflation forecasts for the euro zone only modestly, by less than some had hoped.

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Mike Dolan, Markets Editor EMEA.

(Additional reporting by Sudip Kar-Gupta; Editing by Toby Chopra)

By Atul Prakash