The S&P 500 could hit a new record high thanks to tech and bank stocks, BMO investing chief says

• The S&P 500 index could jump a further 13% by year-end in a bull-case scenario, according to BMO's top strategist.
• Better-than-expected tech and bank earnings in the fourth quarter would power the benchmark index higher in that scenario, Brian Belski said.

The S&P 500 could jump another 13% to hit a record high by the end of the year thanks to better-than-expected tech and bank stock earnings, according to BMO's investing chief.

Brian Belski said Friday that his base case would see the benchmark index hover around its current level for the rest of the year – but laid out a more bullish scenario where fourth-quarter earnings surprises drive it past its current all-time high of just under 4,800 points.

"Our bull case is 5,050 – meaning brand new price highs on the S&P 500," Belski, who is BMO Capital Markets' chief investment strategist, told CNBC's "Squawk on the Street".

"What we believe could drive that is surprising earnings growth, especially in the fourth quarter," he added, citing tech, communications, and financials as the three sectors that could post better-than-expected results.

Financial stocks hit headlines for the wrong reasons earlier this year when the collapse of Silicon Valley Bank in March triggered a crisis for regional lenders.

But tech and communications stocks have fared much better, with the so-called "Magnificent Seven" all racking up stellar returns and iShares' Core S&P 500 UCITS exchange-traded fund, which tracks the latter of the two sectors, up 18% year-to-date.

Belski's 5,050-point price target would see the S&P 500 carry on its stellar run from the first half of 2023, with the gauge up 16% already this year.

Many analysts have pointed to the rise of AI as the key driver behind the stock-market rally – but Belski believes that both equities and fixed-income assets have instead entered a "normalization phase" as the Federal Reserve reaches the end of its tightening cycle, after offering dismal returns in 2022.

"We actually think that this is all part of the normalization phase where you have 10-year Treasury [yields] in the 3% to 4% range, earnings growth in a high single-digit range, market performance in high single-digit or low double-digit range," he told CNBC.

"That's a really great position to have in both bonds and stocks going forward for at least the next three to five years," Belski added.

Read more: The AI boom has powered tech stocks to their strongest start to a year since 1983