* Italy PM says wanted bigger EFSF but several countries refused
* Criticises Cameron, says UK "contemptuously excluded itself"
ROME Dec 11 (Reuters) - Italian Prime Minister Mario Monti said Germany and other countries will eventually be convinced that commonly issued euro zone bonds are a useful way of tackling the region's debt crisis.
"I believe we have enough arguments to convince the Germans," Monti told Euronews in a television interview.
He said Germany should understand it is better to commonly issue debt as a "deliberate and conscious act, rather than as an afterthought and in a way forced, through the purchase by the European Central Bank of bonds of countries in difficulty".
Monti said he regretted that European leaders had not agreed to increase the European bailout fund (EFSF) by more than 500 billion euros ($668.25 billion)at last week's meeting in Brussels.
A more substantial firewall would have been a better guarantee against market tensions, he said, adding this had been blocked by several European countries that "have a very limited view of what is the common interest".
He called the result of the summit "not optimal but very good" and criticised British Prime Minister David Cameron, who refused to sign up to a commitment by the other 26 EU countries to draft a new treaty with tougher fiscal rules.
"If the UK hadn't contemptuously excluded itself it would have been a United Kingdom that counts for more, with more influence," Monti said.