By Noreen Burke

Investing.com -- The escalating energy row between Moscow and the West is set to occupy investors’ attention in the week ahead after Moscow vowed to keep its main gas pipeline to Germany shut. The European Central Bank is set to deliver a big rate hike to combat soaring inflation. Federal Reserve Chair Jerome Powell is due to make an appearance before the central bank goes into its blackout period before its next meeting. Stocks will likely remain volatile as traders return after the Labor Day holiday and OPEC+ is meeting Monday to discuss cutting output to support oil prices. Here's what you need to know to start your week.

1. Energy row

The standoff over Russian gas and oil exports escalated Friday after Moscow vowed to keep its main gas supply pipeline to Germany shuttered and G7 countries announced a planned price cap on Russian oil exports aimed at hitting Russian resources to fight the war in Ukraine.

The latest Nord Stream pipeline shutdown, which Russia says will last for as long as it takes to carry out repairs, added to fears of winter gas shortages that could pull major economies into recession and lead to energy rationing.

Europe has accused Russia of weaponizing energy supplies in what Moscow has called an "economic war" with the West in the wake of Russia's invasion of Ukraine. Moscow blames Western sanctions and technical issues for supply disruptions.

The European Commission has warned that a full cut-off of Russian gas supplies to Europe, if combined with a cold winter, could reduce GDP across the European Union by as much as 1.5% if countries did not prepare in advance.

2. ECB rate hike

The ECB looks set to deliver a second large rate hike at its upcoming meeting on Thursday with inflation in the Eurozone, already at record highs, rapidly approaching double digits.

Eurozone inflation hit a high of 9.1% in August, well above the ECB’s 2% target as soaring energy bills exacerbate a cost-of-living crisis.

The only question for investors is whether the central bank will deliver another 50-basis-point hike, as it did in July, or opt for an even bigger 75-basis-point increase, despite the looming prospect of a recession this winter.

In a recent speech, ECB board member Isabel Schnabel urged central banks to act forcefully to curb inflation, even if that drags their economies into a recession.

3. Fedspeak

Fed Chair Jerome Powell is to speak at a Cato Institute conference on Thursday and investors will be on the lookout for any indications that the Fed is leaning towards another 75-basis-point rate hike at its September 20-21 meeting or whether a 50-basis-point hike may be on the cards.