Shares in online search engine giant, Google rose by close to 12 percent in after-hours trading on Wall Street last night to hit a new record high of $645 per share.

This followed the company’s announcement of a 17 percent jump in second quarter profits to $3.9bn and earnings per share of just under $7c per share, ahead of market expectations.

The group’s new Chief Financial Officer, Ruth Porat, also provided comfort to investors on two key issues -  Google’s performance in relation to paid online ads and how its online video subsidiary, YouTube is faring in the face of growing competition from Facebook

Paid clicks on ads rose by 18 percent during the quarter to June - though revenue per-ad fell.

Total views on YouTube rose by 60 percent during the period, the highest growth rate in two years.

This is the company's first quarter under its new CFO, Ruth Porat - she has pledged to improve its financial discipline and to control costs.

Speaking to investors she said, "A key focus is on the levers within our control to manage the pace of expenses while still ensuring and supporting our growth."

"We will do this while we continue to invest in engineering talent to keep us preeminent in innovation globally," she continued.