(Adds details on Iran operations)

July 17 (Reuters) - Schlumberger NV , the world's No.1 oilfield services provider, said it would look at returning to Iran once the sanctions are lifted.

"When the sanctions are lifted and when it is permissible, we will evaluate going back in," Chief Executive Paal Kibsgaard said on a post-earnings call.

Iran's agreement with major world powers to curtail its nuclear program in exchange for the lifting of some sanctions could open up the world's fourth-largest oil reserves and second-largest natural gas reserves to multi-national oil companies.

However, not all sanctions would be lifted and those that are removed can be rapidly restored if the deal falters.

Schlumberger agreed in March to pay a $237.2 million fine after pleading guilty to violating U.S. sanctions on Iran and Sudan.

The company ceased operations in Iran in the second quarter of 2013, four years after deciding to stop bidding for new Iranian oilfield work.

However, some non-U.S. affiliates of the company continued to work for the National Iranian Oil Co or its units. Revenue from the work totaled $418 million in 2012, accounting for about 4 percent of total revenue that year.

Schlumberger reported a better-than-expected profit on Thursday as stringent costs controls helped offset revenue declines caused by a steep fall in oil prices.

The company's shares were little changed at $84.95 in morning trade on the New York Stock Exchange.

(Reporting by Swetha Gopinath in Bengaluru; Editing by Sriraj Kalluvila) ((swetha.gopinath@thomsonreuters.com; within U.S. +1 646 223 8780, outside U.S. +91 80 6749 1130; Reuters Messaging: swetha.gopinath.thomsonreuters.com@reuters.net))

Keywords: SCHLUMBERGER RESULTS/IRAN