(Recasts lead, adds reaction of the presidential press office in paragraph 2)

KIEV, May 17 (RIA Novosti) - Ukraine's presidential secretariat said the Constitutional Court, which honored a resignation plea from its chairman amid an ongoing feud between the president and prime minister earlier Thursday, is legally nonexistent.

"How can we talk about any decisions [of the Constitutional Court] if there is no quorum?" said Ihor Pukshin, deputy head of the presidential secretariat, citing three of court's 18 judges dismissed and four officially on the sick list. "The situation in which a Constitutional Court chairman resigns demonstrates that we do not have such an institution at all."

A pro-presidential judge in the 18-member Constitutional Court, which is looking into President Viktor Yushchenko's decree to dissolve parliament and call early elections, Dombrovskiy was reported to have already tendered his resignation April 4, to no avail.

Valery Pshenychniy, reinstated as a Constitutional Court judge by a court decision May 16 after Yushchenko dismissed him in late April, was appointed acting chairman.

Yushchenko disbanded parliament, dominated by Prime Minister Viktor Yanukovych's supporters, in late April and called snap polls, accusing the premier of "usurping power." Yanukovych earlier opposed polls, but eventually agreed.

But the factions have not yet coordinated laws to allow the vote, or its date. They had earlier planned to announce the date on May 16.