The chief executive of French advertising agency Publicis has said the lengthy negotiations with China regarding its merger with Omnicom Group is taking energy out of the day to day running of the firm, but Chinese authorities are not asking any "embarrassing questions".
CEO Maurice Levy said he was still confident the merger would go ahead as planned, but the process is "long and slow".
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"The process is long and slow, we have no big worries, apart from the fact it is taking time and energy out of the day to day business," he told CNBC as the group announced their results for the first quarter this year.
The advertising agency posted gains in revenue growth in the first quarter, as business in European turned around and sales picked up in China.
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The group achieved 3.3 percent organic growth compared to 0.7 percent at the end of last year and revenue came in at 1.6 billion euros ($2.21 billion), in line with a poll of Reuters analysts' expectations.
Levy confirmed Publicis' annual targets of organic sales growth of more than 4 percent and improved operating margins and shares rallied over 5 percent higher after the results.
"Last year we had a real problem with China, where we had double digit negative growth for the last quarter, as a lot of advertising had been stopped particularly in luxury goods. This year first quarter, we are up – which is extremely positive," he told CNBC.
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Levy, who has served as Publicis CEO since 1987 and led the group to the merger with U.S. conglomerate Omnicom to create the world's largest advertising firm, had expected the merger to be completed by the first quarter of 2014.
The merger is currently waiting approval from Chinese regulators, after receiving the all clear from Europe and U.S. and is now expected to be finalised in the Q3 this year.
"We have filed a pre-filing, they are putting questions and we are answering and the iteration goes on like this. We don't see any question which is really embarrassing - we have the answers pretty quickly and they are reacting pretty quickly also," he said
"I don't believe that it is a big hurdle other than the time it is taking," he added.
Levy expects a "very strong" Brazil due to the upcoming World Cup, but said he was concerned about what will happen in India because of the elections taking place.