Saudi Arabia's bourse halts a two-session climb as banks weigh, while Orascom Construction Industries (OCI) helps lift Egypt's bourse.
Saudi lender SABB slips 0.3 percent. Arab National Bank and Alinma Bank shed 0.7 and 0.4 percent respectively.
Banks posted mixed earnings, some missing analysts' average forecasts, spurring investors to reduce positions.
Shares in Abdullah A M Al Khodari Sons Company plunge 6.5 percent to a two-week low. The construction firm said late-Saturday its fourth-quarter net profit dropped 50 percent, mainly due to direct cost impact. Its net income fell in a rapidly-evolving labour market because of reinforced efforts by the authorities to encourage Saudisation through its Nitaqat programme and delays in visa issuance.
The labour ministry said in November that companies employing more expatriate workers than Saudis will be fined a fee of SAR2,400 (US$640) a year for each excess foreigner.
"We feel that faster execution of projects led to a rise in revenues. But at the same time, growth in the order book did not keep pace with project execution," Hettish Karmani, senior financial analyst at Global Investment House, says in a note.
The kingdom's index slips 0.1 percent to 7,046 points, trimming January gains to 3.6 percent.
In Egypt, OCI climbs 1.4 percent, having risen 3.7 percent in early trade. US investors have committed US$1bn to buy a stake in OCI's construction and fertiliser unit OCI NV, in one of the largest foreign currency inflows to Egypt since the 2011 revolution that swept Hosni Mubarak from power.
Commercial International Bank Egypt advances 1.6 percent. Orascom Telecom (OT) climbs 1.8 percent but shares in the telecom operator are suspended pending clarification on news related to Canada's upstart Wind Mobile.
Anthony Lacavera, founder of Wind Mobile, plans to step down as chief executive as part of a deal that will give Egypt's OT control of the carrier, the Canadian firm said.
Cairo's benchmark rises 0.9 percent to 5,714 points, heading for its third gain in the last seven sessions.