"Tensions in Ukraine are clearly having an impact on confidence, subduing business spending and investment," said Chris Williamson, Markit's chief economist.
Separately Wednesday, the European Union's statistics office, Eurostat, said eurozone retail sales fell by a monthly 0.4 percent in July.
The figures echo a raft of recent findings that any momentum that the eurozone economy may have been showing earlier in the year came to a halt through the summer. In the second quarter, the eurozone economy posted flat growth, raising fears of an unprecedented triple-dip recession.
The hope in Europe will now be that those tensions which have been hobbling Europe's economy will ebb following Wednesday's apparent agreement by Ukraine President Petro Poroshenko and Russian President Vladimir Putin to call a halt to the fighting in eastern Ukraine.
Though details of the cease-fire agreement are sketchy and there was no immediate indication that the fighting would stop, investors around Europe have responded positively to the news. The Stoxx 50 index of leading European shares was up 0.9 percent, while Germany's DAX spiked 1.1 percent. Unsurprisingly, Russia's RTS index was the standout performer, trading 3.9 percent higher.
Germany's economy, Europe's biggest, has been one of the most affected by the escalation in tensions over Ukraine this year. Germany has a big trading relationship with Russia that has been threatened by the tit-for-tat sanctions that have been exchanged between Moscow and the European Union.
It's unclear whether the cease-fire agreement will have any bearing on Thursday's monthly meeting of the European Central Bank. There are some expectations in the markets that the ECB, headed by President Mario Draghi, may back further measures to stimulate the ailing eurozone economy. There's even been talk that it could back a Federal Reserve-style program to inject new money into the economy.
Markit's Williamson said it's "likely to be too early" to see anything other than stronger rhetoric from the ECB as far as a stimulus is concerned, especially as the firm's survey is pointing to strong growth in Ireland and Spain, two of the countries at the forefront of the region's debt crisis.
He said the impressive performances of the two will likely encourage Draghi to "stress that recoveries in other countries are being held back by the lack of successful structural reforms rather than a lack of central bank stimulus."