The supervisory board of Germany's second biggest lender Commerzbank is discussing possible capital measures on Wednesday with a significantly larger volume than previously expected, a company source told Reuters.

Commerzbank declined to comment.

Two sources had told Reuters on Tuesday that Commerzbank invited banks to pitch for an accelerated capital increase of up to 10 percent, or 700-800 million euros (609 million pounds).

Shares in Commerzbank, which received a state bailout in the 2009 financial crisis, extended losses and traded 4 percent lower at 1.34 euros by 0846 GMT.

(Reporting by Alexander Hübner; Writing by Arno Schuetze; Editing by Maria Sheahan)