The FTSE 100 <.FTSE> clocked up solid gains on Tuesday as upbeat corporate earnings reports provided some relief from ongoing concerns about a sovereign debt crisis in the euro zone's periphery.

Banks <.FTNMX8350> rebounded from two days in the red, with Lloyds Banking Group , up 7.8 percent, leading the charge after reiterating its guidance on full-year margin and provisions in its third-quarter trading update.

The part-state-owned bank, whose chief executive is on temporary sick leave, posted a third-quarter loss and said it may miss some financial targets due to the economic turmoil

Among other well-received earnings, Vodafone , up 2.3 percent, added the most index points after the mobile phones firm raised its full-year outlook on the back of strong first-half results, boosted by growth in India and robust performances in Germany and Britain.

Marks & Spencer benefited as well from an earnings boost, ahead 4.2 percent, with the clothing and food retailer seeing its first-half profit before tax and one-off items ahead of consensus forecasts.

With much of the retail pain already priced in, the numbers have come as a welcome relief to M&S investors, said Richard Hunter, Head of Equities at Hargreaves Lansdown Stockbrokers.

The FTSE 100 index was up 66.80 points, or 1.2 percent at 9:34 a.m. at 5,577.82 largely offsetting losses in the two previous sessions, although volumes were fairly light at just 23.50 percent of their average in the last 90 days.

If you strip out RBS and Lloyd's there are virtually no volumes today. It's all short-term trades, there's no real money coming in from the sidelines, said Joe Rundle, head of trading at ETX Capital.

Strength in heavyweight miners <.FTNMX1770> and energy <.FTNMX0530> stocks also provided support for the blue chips, as copper and crude oil prices pushed higher.

Cairn Energy added 3.1 percent in strong volumes after announcing it has found oil in the Atammik block, offshore Greenland.

However, in spite of the market's upbeat mood, commentators were still cautious.

Short-term sentiment can flip... All the focus is on Italy today and we're looking at the vote later, ETX's Rundle added.

Italy, the third biggest economy in the euro zone, faces a crucial vote on public finance in parliament later this morning and the centre-left opposition said it was preparing a motion of no-confidence in the government that would bring Berlusconi down even if he should survive Tuesday's vote.

(Editing by Mike Nesbit)