* FTSE 100 flat, mid caps down 0.1 pct
* Results weigh on Whitbread
* Carillion jumps on credit deal (Adds details, closing prices)
LONDON, Oct 24 (Reuters) - Firmer commodities-related stocks barely kept the UK's top share index out of negative territory on Tuesday as results depressed Whitbread, though small cap Carillion saw its shares boosted by progress with its debt.
Britain's blue chip FTSE 100 index ended flat at 7,526.54 points and mid caps fell 0.1 percent.
"Away from politics, it's been quiet on the Brexit front, so I think British investors are looking more at earnings season," said Henry Croft, research analyst at Accendo Markets. Upcoming results from banks will be closely watched, he added.
Results weighed on Whitbread's shares which dropped 4.8 percent to bottom of the index.
While the hotel and coffee shop operator saw a rise in first-half profit, analysts were concerned around signs of an impact from last year's Brexit vote on the business.
"We remain attracted to the long-term growth prospects for Whitbread, but acknowledge that the potential woes for UK businesses and consumers due to Brexit will make for a bumpy ride," analysts at Berenberg said in a note.
On the positive side, Antofagasta, up 2.8 percent, was the biggest gainer among commodity stocks after Barclays raised its price target on the stock.
Shares in RSA Insurance rose as much as 2 percent after JP Morgan raised its rating on the stock to "overweight" from "neutral".
"RSA has underperformed in recent months and in our view its valuation again looks attractive," analysts at JP Morgan said in a note, adding that they believe the pricing backdrop in commercial lines may improve after recent natural catastrophes.
Results were also front and centre of the action among smaller stocks. Shares in mid cap oil services firm Hunting jumped 8.8 percent after its third-quarter trading statement.
Troubled small cap Carillion rose 6.3 percent after saying that it had agreed new credit facilities and deferrals on some debt repayments, as well as disposing part of its UK healthcare business to Serco.
"We view both of these developments as incrementally positive in improving the near-term cash position," analysts at Stifel said in a note.
Carillion's shares have slumped around 80 percent this year following two profit warnings.
(Reporting by Kit Rees; Additional reporting by Danilo Masoni; Editing by Jon Boyle and Pritha Sarkar)