Design and engineering firm WS Atkins expects its U.S. business to hit high growth levels in its 2014 fiscal year, as it seeks to tap into a surge in infrastructure spending and grab market share, its chief executive told Reuters.

Atkins, which helped design the London 2012 Olympics site and is renovating New York's Statue of Liberty, upped its overseas exposure in 2010 with the 178 million pound acquisition of U.S. firm PBSJ Corp, lifting the North America region to over 20 percent of group sales.

The firm now aims to extend its international reach in markets like the Middle East and Scandinavia as well as the United States, with Britain expected to account for about a quarter of group sales in three years from 48 percent now.

While the Middle East is still a growth engine it is a difficult market to play in, Chief Executive Uwe Krueger, who joined the FTSE 250 firm in July, said in an interview.

The opportunities in the U.S. are clearly an important focus to us. It is such a huge infrastructure and engineering market that now, with the bridge that we have in PBSJ, we want to expand faster.

Atkins, which is around the 12th biggest player in what is still a flat U.S. market, said it stood to benefit from America's plans to boost infrastructure spend, such as President Barack Obama's proposal to put war savings into high-speed rail lines and road repairs and a newly created $25 billion infrastructure bank in New York.

We have a very solid basis for growth (in the U.S.), you probably won't see that happening in exactly the next business year - we will see margin improvements but we will not see a high growth curve next year. The year after (2014), I am very hopeful, Krueger said.

The group, whose fiscal year runs to end-March, said the Middle East would continue to offer near-term high growth potential as countries like Qatar and Saudi Arabia unleash huge infrastructure spends and energy and oil and gas markets expand.

In Britain, where with Skanska the group recently won a highways deal worth 400 million pounds, Krueger said trading would remain stable, but added he did not see much growth.

Atkins, which employs around 18,000 people, wants to expand its businesses in all of its core areas of energy, defence, water and aerospace and said it is looking for acquisitions which typically cost no more than 50 million pounds, but did not rule out game changing opportunities if one were to arise.

Across its core markets the group has worked on design projects from Dubai's Jumeirah Beach hotel to the carbon structure of wings on the Airbus A380 superjumbo. In energy it provides oil platform safety engineering and designs offshore wind stations.

The group is expected to report 2011-2012 pretax profit of 100.42 million pounds, according to a consensus of 14 analysts polled by Reuters.

(Editing by Mark Potter)