KIEV, Ukraine (AFP) -- Ukraine's parliament erupted into chaos yesterday as deputies scuffled and hurled smoke bombs during a tumultuous session that ratified a bitterly contested deal with Russia extending a naval base lease.

Despite the extraordinary scenes that saw parliament --the Verkhovna Rada -- filled with smoke, lawmakers ratified the deal to extend the stay of the Russian Black Sea fleet until at least 2042, denounced by the opposition as a sell-out for Ukraine.

The uproar started when the parliament speaker, Volodymr Lytvyn, was pelted with a volley of a dozen eggs, forcing him to duck for cover behind black umbrellas held by two aides.Several smoke bombs were thrown, apparently by pro-Western opposition deputies, filling the chamber with smoke. Some deputies covered their faces or held handkerchiefs to their noses as alarms sounded.

A fistfight broke out on the deputies' benches and one lawmaker was seen thumping a colleague on the head. Another gripped a fellow deputy in a headlock as others piled in with eager punches.

Deputies also started fighting over a massive Ukrainian flag in the middle of the chamber, twisting and distorting the yellow and blue banner as smoke kept billowing.

Andriy Shevchenko, a member of parliament from the bloc headed by former prime minister Yulia Tymoshenko, acknowledged that the smoke bombs were thrown by "our deputies".

But he called the action justified. "History will be our judge," Shevchenko said. "In principle, the mood was to use all means possible short of guns."

Amid the chaos, some deputies tried to push on with business and give their floor speeches as if nothing extraordinary was taking place.

While some shouted "Shame, Shame!" the parliament ratified the pact with Moscow, 236 lawmakers voting in favour of the deal in the 450 seat chamber.

"Neither smoke bombs, egg-throwing, nor fighting is going to prevent the majority from taking its decisions," said Prime Minister Mykola Azarov after the session.