Mexico peso up by most in 3 months on Greek hopes

* Greek hopes lift peso by most since Oct. 29

* Stocks rise, helped by Grupo Mexico

* Cemex shares slump after unexpected executive shuffle

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MEXICO CITY, Feb 9 (Reuters) - Mexico's peso rallied the most in three months on Tuesday and stocks jumped on news euro zone countries may have decided to help debt-stricken Greece, boosting investor appetite for riskier emerging market assets.

The peso MXN=MEX01 gained 1.71 percent to 13 per U.S. dollar, its biggest one-day jump since Oct. 29, while the IPC stock index .MXX closed up 0.55 percent at 30,818.48.

European governments have agreed in principle to help heavily indebted Greece, a senior German coalition source said on Tuesday, in what would be the first rescue of a euro zone member in the currency's 11-year history. For details see [ID:nSGE61801C]

Rising debt in Greece, Portugal and other euro zone states could undermine a global recovery, analysts say. Worries of a sovereign debt default in Europe pushed investors to dump riskier assets in recent weeks.

"Finally they are deciding to get together to try and find a solution for Greece. But we still have to see how big and what it consists of," said a trader in Mexico City.

The reports of aid came two days before a European Union summit that is expected to address the Greek debt crisis.

Traders said that could keep the peso's gains contained on Wednesday as markets wait to see if a bailout materializes. Traders said the peso could firm sharply toward 12.80 per U.S. dollar if markets approve of a Greece package.

But some were skeptical that markets have seen an end to the nervousness that sank the euro to an 8-1/2 month low last week.

"I don't doubt that European governments have good intentions, but with what money?," said Alfredo Puig, a trader at Vector brokerage in Monterrey. "The problem is too big. It isn't just Greece, but Spain and Portugal."

Appetite for the euro is often a bellwether for emerging market currencies. Mexico's peso has lost around 4 percent since Jan. 19 amid rising worries about Europe's troubles.

Mexican stocks have been hammered down more than 6 percent from an all-time high hit in early January.

On Tuesday, copper producer Grupo Mexico (GMEXICOB.MX) rose 1.31 percent to 27.78 pesos as the weaker dollar fueled higher commodity prices and a top executive said a court could soon rule in its favor on a two-year old strike. [ID:nN0987456]

Cement maker Cemex (CMXCPO.MX) lost 2.07 percent to 12.30 pesos after it unexpectedly announced that its No. 2 executive was retiring. [ID:nN0996262]

The government's benchmark 10-year peso bond MX10YT=RR was bid down 4 basis points to yield 7.70 percent. Traders said global investors looking for higher yields than those available in developed economies were snatching up bonds, eyeing the peso's recent depreciation as a good entry level.

Many analysts see the peso firming back below 13 per dollar toward one-year highs hit last December around 12.50, helped by a rebound in Mexican exports as the U.S. economy recovers. (Reporting by Michael O'Boyle; Editing by Dan Grebler)