NEW YORK, USA: Telecom equipment maker Nokia Siemens Networks is not planning an offer for U.S. gear maker Ciena Corp, a source close to NSN said, despite market speculation of a deal.

Ciena attracted bullish options activity on Tuesday on rumors Nokia Siemens, a joint venture of Nokia Oyj of Finland and Siemens AG of Germany, will buy Ciena, analysts said.

Both Ciena and Nokia Siemens declined to comment.

Ciena shares were up 5.6 percent at $11.63, and the overall option volume was four times greater than its recent average daily turnover, according to option analytics firm Trade Alert.

Ciena last month trumped an offer by Nokia Siemens and its financial partner, One Equity Partners, to buy the optical networking and carrier ethernet unit of bankrupt Nortel Networks Inc.