RIGA (AFP) - Latvia's ruling centre-right coalition led by Prime Minister Laimdota Straujuma scored a resounding majority in Saturday elections overshadowed by alarm over a resurgent Russia and a Kremlin-allied party.

An exit poll by the SKDS agency gave three parties in her coalition 63 seats in the 100-member parliament, while their pro-Kremlin rival took 23.

"This is a vote of confidence in (Straujuma's) Unity party and in the coalition... it means people want us to continue our work," parliamentary speaker Solvita Aboltina and Unity party chair told Latvian public broadcaster LTV.

Unity scored 25 seats while its coalition partners National Alliance and the Greens and Farmers scored 19 seats each respectively, according to SKDS.

Nils Usakovs, leader of the Kremlin-allied opposition leftist Harmony party which exit polls showed came second with 23 seats called the result "positive".

"We will wait until the morning to see the result. We shouldn't rely on exit polls," he told LTV.

"This is more of the same coalition, but it's slightly changed in the balance of power and that makes Unity more powerful," University of Latvia Professor Ivars Ijabs told AFP.

"The probability that we will see someone other than Straujuma as prime minister is quite high," he added.

It was not immediately clear whether President Andris Berzins would ask Straujuma, a technocrat, to form a fresh coalition government.

"On the prime minister we will have to wait and see who the president decides to nominate," Aboltina said.

Analysts in Riga believe Berzins could tap her Unity party colleague, outgoing EU development commissioner Andris Piebalgs, for prime minister as Latvia is poised to take over the European Union's rotating six-month presidency in January.

Russia's annexation of Crimea and meddling in eastern Ukraine have sent shudders through this NATO and eurozone member of two million people where many retain vivid memories of the Soviet occupation that ended just a quarter-century ago.

With Europe now in its worst standoff with Russia since the Cold War, many Latvians fear Moscow could attempt to destabilise its Soviet-era Baltic backyard.

Berzins insisted after casting his vote that "military safety and Nato... internal stability, peace and, of course, stable economic growth are our priorities".

A pragmatic technocrat, 63-year-old Straujuma has called for more Nato troops and extra air patrols in the region.