Russia's Daniil Medvedev says he "feels sorry" for Ukrainian players competing on tour amid the ongoing war.

Women's world number one Iga Swiatek has also called for more support for competitors from Ukraine, which was invaded by Russia in February 2022.

"I'm for peace all over the world, I've always said the same," Medvedev said.

Russian and Belarusian players have been allowed to compete on both men's and women's tours as individual athletes without national affiliation while the conflict continues.

"I definitely do feel sorry for all the Ukrainian players and what they go through," world number six Medvedev said.

"Of course we have a responsibility (to talk about the issue) and it depends how every person, individual, will do it."

The 27-year-old reached the men's semi-finals in California on Wednesday night with his 18th consecutive tour win, beating Spain's Alejandro Davidovich Fokina 6-3 7-5.

But the 2021 US Open champion declined to comment at length on the specific issue between Tsurenko and Sabalenka, saying the subject was a matter for the players involved to speak about.

Medvedev, who has won ATP titles in Rotterdam, Doha and Dubai in the past month, will face Frances Tiafoe in the semi-finals after the American beat British number one Cameron Norrie in straight sets.

Sabalenka into semis as Swiatek backs Tsurenko

Sabalenka, who won her maiden Grand Slam title at this year's Australian Open, moved into the women's semi-finals with a dominant 6-4 6-0 victory over American Coco Gauff.

The world number two had received a bye in the previous round when scheduled opponent Tsurenko pulled out of their match.

The Ukrainian said she had suffered a panic attack after a chat with Women's Tennis Association (WTA) chief executive Steve Simon about tennis's response to Russia's invasion.

The WTA had issued a formal warning to Russia's Anastasia Potapova, 21, for wearing a Spartak Moscow football shirt before her match against Jessica Pegula earlier in the week.

Three-time Grand Slam champion Swiatek, who could face Sabalenka in the final at Indian Wells, supports Tsurenko's decision.

"I totally understand why she withdrew," said Poland's Swiatek, who plays Romania's Sorana Cirstea in the quarter-finals on Thursday.

"I respect Ukrainian girls so much, because if like a bomb landed in my country or if my home was destroyed, I don't know if I could handle that, honestly, and play on the WTA and compete.

"I feel there should be a little bit more done to help Ukrainian players - everything we discuss in tennis is more about Belarusian and Russian players, if they should be allowed, what's going on with them.

"We should focus on helping Ukrainian players and providing them everything they need, because they basically have to take care of all their families, and there's a lot of baggage on their shoulders."

Elsewhere, Rafael Nadal has entered the clay-court Monte Carlo Masters next month as he prepares to return to action following a hip flexor problem.

The 22-time Grand Slam champion has not played since sustaining the injury in his Australian Open second-round defeat by Mackenzie McDonald in January.