The largest U.S. advertising company reported a 3.2 percent rise in domestic revenue to $1.82 billion in the third quarter, making up half of total revenue.

Omnicom reported net income of $196 million, or 74 cents per share, in the three months ended September, compared with $203.9 million, or 74 cents per share, a year earlier.

The company said the results included $28.1 million of pre-tax charges related to the proposed merger with Publicis Groupe SA. Excluding the merger expense, Omnicom earned 82 cents per share.

Revenue rose 2.5 percent to $3.49 billion.

Analysts on average had expected earnings of 80 cents per share on revenue of $3.48 billion, according to Thomson Reuters I/B/E/S.

Omnicom, home to agencies such as BBDO Worldwide and Goodby, Silverstein & Partners, creator of the "Got Milk?" campaign, announced the $35.1 billion merger with France-based Publicis in July.

Publicis expects the deal to close in the fourth quarter of 2013 or the first quarter of 2014.

Omnicom's shares were up more than a percent in premarket trading on Tuesday. They closed at $63.95 on the New York Stock Exchange on Monday.