May 17 (Reuters) - French steelmaker Vallourec topped first-quarter core earnings expectations on Wednesday, aided by strong sales of steel tubes and iron ore, sending its shares up 8%.

The group's earnings before interest, tax, depreciation and amortisation (EBITDA) jumped more than sevenfold to 320 million euros ($352 million).

The group cited tube sales totalling 431 million tonnes and a strong increase in iron ore mine production sales to 1.5 million tonnes from 0.1 million tonnes last year, driven by solid mining activity in Brazil.

In January last year, Vallourec temporarily suspended operations in its Pau Branco iron ore mine in Brazil due to flood-related damage. Earlier this month, it said the mine would return to full production by the end of the current quarter.

"We are already well advanced in the resumption of full production at this mine and all the work undertaken to improve the profitability of the tube activity is obviously continuing to bear fruit and will continue to do so in Q2," CEO Philippe Guillemot said.

Vallourec said it expected second-quarter EBITDA to be similar to the first quarter, and reiterated 2023 outlook.

The group said its restructuring plan, which prioritises margins over volumes, was fully on track to generate 230 million euros of recurring EBITDA and to reduce capital expenditures by around 20 million euros from the second quarter of 2024.

Vallourec said it was ramping up investments in Brazil to ensure the relocation of its oil and gas activities this year after closing its manufacturing sites in Germany.

The group's revenue rose 46% to 1.34 billion euros in the quarter. ($1 = 0.9084 euros)

(Reporting by Dina Kartit in Gdansk; Editing by Milla Nissi and Christina Fincher)