Russian negotiators flew to Turkey to hold peace talks with Ukraine on Wednesday, the Kremlin said, before what will be the first direct discussions between the warring sides in more than seven weeks.

Russia played down expectations of any breakthrough at the meeting, which Ukrainian President Volodymyr Zelenskyy said this week should focus in part on preparing a summit between himself and President Vladimir Putin.

"Naturally, no one expects an easy road. Naturally, this will be a very difficult conversation. The projects [of each side] are diametrically opposed," Kremlin spokesperson Dmitry Peskov told reporters.

The warring sides held two previous rounds of talks in Istanbul — on May 16 and June 2 — that led to the exchange of thousands of prisoners of war and the remains of dead soldiers.

But they have made no breakthrough toward a ceasefire or a settlement to end almost three-and-a-half years of war.

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Trump’s Russia-Ukraine ceasefire deadline met with skepticism

U.S. President Donald Trump’s 50-day deadline for Russia to agree to a ceasefire is being met with skepticism in Ukraine, but people are hopeful more military support could be on its way.

U.S. President Donald Trump last week threatened heavy new sanctions on Russia and countries that buy its exports unless a peace deal was reached within 50 days.

But three sources close to the Kremlin told Reuters that Putin, unfazed by Trump's ultimatum, would keep on fighting in Ukraine until the West engaged on his terms for peace, and that his territorial demands may widen.

Russia presses on in eastern Ukraine

Fierce fighting rages along more than 1,000 kilometres of the front line. Russian troops continue their grinding advance in the east and have stepped up near-daily attacks on Ukrainian cities with hundreds of drones.

On Wednesday, Russia said its forces had captured the settlement of Varachyne in Ukraine's Sumy region, where Putin has ordered his troops to create a buffer zone after Ukraine mounted a shock incursion into Russia last year and held onto a chunk of its territory for months. Reuters could not independently confirm the battlefield report.

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Why Russian drones are getting harder to shoot down

Russia is using upgraded weapons to launch its escalating attacks on Ukraine. These drones are designed to cause even more destruction and are even harder to shoot down. CBC’s Briar Stewart explains.

Ukraine has hit back with attacks of its own, and last month inflicted serious damage on Russia's nuclear-capable strategic bomber fleet by smuggling drones close to airbases deep inside the country.

Zelenskyy said earlier this week that the agenda for talks was clear: the return of prisoners of war and of children abducted by Russia, and the preparation of a meeting between himself and Putin.

Putin turned down a previous challenge from Zelenskyy to meet him in person and has said he does not see him as a legitimate leader because Ukraine, which is under martial law, did not hold new elections when Zelenskyy's five-year mandate expired last year. Russia also denies abducting children.

At the last meeting, Russia handed Ukraine a memorandum setting out its key demands, including: full withdrawal of Ukrainian forces from four regions of the country that Russia has claimed as its own; limits on the size of Ukraine's military; enhanced rights for Russian-speakers in Ukraine; and acceptance by Kyiv of neutral status, outside NATO or any other alliance.

Ukraine sees those terms as tantamount to surrender; Zelenskyy described the Russian stance as an ultimatum.

Ukraine wants an immediate ceasefire, reparations, international security guarantees and no restrictions on its military strength.

Protests against Ukraine government move

Meanwhile, Zelenskyy is facing dissent politically within Ukraine to a degree not seen since Russia invaded in early 2022, after a law curbing the independence of anti-graft agencies triggered street protests and rare rebukes from European allies.

Opposition lawmakers and European officials on Wednesday called for Kyiv to reverse the law, which Zelenskyy just signed overnight. It was rushed through parliament on Tuesday, a day after the security services arrested two anti-corruption officials for suspected Russian ties.

In his nightly televised address, Zelenskyy said Ukraine's corruption-fighting agencies — an investigating agency known as NABU and a prosecutor's office known as SAPO — would continue to function "but without any Russian influence."

In the morning, he met officials, including the heads of NABU and SAPO, and said he would unveil a new plan to fight corruption within two weeks.

Several hundred people took to the streets in Kyiv and other large Ukrainian cities late on Tuesday to protest, the first such demonstrations of the war.

"This is complete nonsense from the president's office," Solomiia Telishevska, 20, a student in Kyiv on holiday, told Reuters. "This contradicts what we are fighting for and what we are striving for, namely to [join] the European Union."

After decades when Ukraine was seen as one of the most corrupt countries in the world, cleaning up its government has been held up as the most important condition for Kyiv to join the European Union and integrate more broadly with the West.

Corruption is consistently cited by investors and the general public as one of the key challenges facing Ukraine, as it has traditionally been one of the lowest-ranking developed nations on Transparency International's annual corruption index.